diff --git a/irf.m b/irf.m
index 43de714dc..588dc16be 100644
--- a/irf.m
+++ b/irf.m
@@ -25,6 +25,9 @@
 % version = IRF('version') return IRF version number
 % [versionNumber, versionDate] = IRF('version') return also date
 %
+% [out] = IRF('path') returns the path to the current irfu-matlab root
+% directory.
+%
 % IRF('demo') demonstration how to use IRF
 
 %this is an edit to load BLAS
diff --git a/irf/+irf/+cdf/datevec_to_TT2000.m b/irf/+irf/+cdf/datevec_to_TT2000.m
index 4ef8753b8..8411385fa 100644
--- a/irf/+irf/+cdf/datevec_to_TT2000.m
+++ b/irf/+irf/+cdf/datevec_to_TT2000.m
@@ -22,11 +22,17 @@
 %
 function tt2000 = datevec_to_TT2000(dateVecUtc)
 % PROPOSAL: Separate wrapper function to handle spdfcomputett2000 special case.
-
 % PROPOSAL: Make handle failed conversions when spdfcomputett2000 returns a too low value.
 %   ~CON: spdfcomputett2000 already returns special value.
+%
+% PROPOSAL: Refactor to take datetime as argument.
+%   PRO: More standard time format.
+%   PRO: The only (irfu-matlab) applications so far effectively use datetime as
+%        argument for this function.  /2024-03-05
+%   PRO: Already easy to convert between datetime and date vector.
+%   NOTE: Might want to similarily convert irf.cdf.TT2000_to_datevec().
 
-irf.assert.sizes(dateVecUtc, [NaN,6])
+irf.assert.sizes(dateVecUtc, [NaN, 6])
 
 % IMPLEMENTATION NOTE: Using integer precision is good for automatic testing
 % (empirically it is needed for predictable, reversible results).
diff --git a/irf/+irf/+cdf/write_dataobj.m b/irf/+irf/+cdf/write_dataobj.m
index a1d930340..ab448a24d 100644
--- a/irf/+irf/+cdf/write_dataobj.m
+++ b/irf/+irf/+cdf/write_dataobj.m
@@ -331,7 +331,7 @@ function write_dataobj(filePath, ...
 
   %============================================================================
   % Convert specific VariableAttributes values
-  %
+  % ------------------------------------------
   % Case 1: tt2000 values as UTC strings : Convert to tt2000.
   % Case 2: All other                    : Convert to the zVariable data type.
   % --------------------------------------------------------------------------
diff --git a/irf/+irf/+utils/mixed_radix.m b/irf/+irf/+utils/mixed_radix.m
index de63850ac..f1bd2d97a 100644
--- a/irf/+irf/+utils/mixed_radix.m
+++ b/irf/+irf/+utils/mixed_radix.m
@@ -6,6 +6,8 @@
 % Ex: Can interpret [seconds, milliseconds, microseconds, nanoseconds] as used
 %     by the spdf* TT2000 functions.
 %
+% See e.g. https://en.wikipedia.org/wiki/Mixed_radix .
+%
 %
 % NOTES
 % =====
@@ -21,7 +23,7 @@
 %
 % CONVENTIONS
 % ===========
-% MRD = Mixed Radix Digits, i.e. the digits in mixed radix number.
+% MRD = Mixed Radix Digits, i.e. the digits in a mixed radix number.
 % --
 % iDigit=1 <==> Least significant digit.
 %            NOTE: This means that digits are in the opposite order to what is
diff --git a/mission/solar_orbiter/solo_local_file_db.m b/mission/solar_orbiter/solo_local_file_db.m
index d64a4b398..b51595cd2 100644
--- a/mission/solar_orbiter/solo_local_file_db.m
+++ b/mission/solar_orbiter/solo_local_file_db.m
@@ -103,8 +103,10 @@ function list_sci_tint()
           t.min   = str2double(utc(15:16));
           t.sec   = str2double(utc(18:end-1));
         end
+
         function limited_sci_list()
-          listingD = dir([fullfile(curDir, dPref) '*.cdf']); % SolO have only latest file of each type.
+          listingD = dir([fullfile(curDir, dPref) '*.cdf']); % SolO directories only have the latest version datasets (files).
+
           if isempty(listingD), return, end
           if isempty(dateFormat)
             % Are we looking for files with 8 or the full 14 digits
@@ -190,13 +192,14 @@ function list_sci()
           end
         end
       end % LIST_SCI
+
       %% ADD2LIST_SCI
       function add2list_sci(name,curDir)
         Entry = struct('name', name, 'ver', str2double(name(end-5:end-4)), ...
           'start',[], 'stop',[],...
           'path', curDir, 'dbId', obj.id);
         Entry = add_ss(Entry);
-        % Check time limits of the file
+        % Check if time range in file is within specified time limits.
         if isempty(Entry) || ~isempty(tint) && ...
             (Entry.start>tint.stop || Entry.stop<tint.start)
           return
@@ -211,6 +214,7 @@ function add2list_sci(name,curDir)
         if is_version_larger(str2double(name(end-5:end-4)), fileList(iSame).ver)
           fileList(iSame) = add_ss(Entry); % replace file
         end
+
         function entry = add_ss(entry)
           entryTmp = obj.cache.get_by_key(entry.name);
           if ~isempty(entryTmp)
@@ -230,14 +234,17 @@ function add2list_sci(name,curDir)
             errS = ['Cannot read: ' entry.path filesep entry.name];
             irf.log('critical',errS), error(errS)
           end
+
+          % Search for TT2000-typed zVariables in CDF.
           isCdfEpochTT2000VariableArray=cellfun(@(x) strcmpi(x,'tt2000'), info.Variables(:,4));
           if ~any(isCdfEpochTT2000VariableArray)
             errS = ['no TT2000 vars in:' entry.path filesep entry.name];
             irf.log('critical',errS), error(errS)
           end
-          iVar = find(isCdfEpochTT2000VariableArray,1);
-          data = spdfcdfread([entry.path filesep entry.name], ...
-            'Variables', info.Variables(iVar,1), 'CombineRecords', true, ...
+
+          iTt2000Var = find(isCdfEpochTT2000VariableArray,1);
+          varData = spdfcdfread([entry.path filesep entry.name], ...
+            'Variables', info.Variables(iTt2000Var,1), 'CombineRecords', true, ...
             'KeepEpochAsIs', true, 'DataOnly', true);
           if ispc
             % Add a very short delay to ensure consecutive files are not
@@ -245,10 +252,10 @@ function add2list_sci(name,curDir)
             % hard crash on Win10 regardless of the try&catch.
             pause(0.0001);
           end
-          if isempty(data), entry = []; return, end
-          entry.start = EpochTT(data(1));
-          entry.stop = EpochTT(data(end));
-          % add to cache
+          if isempty(varData), entry = []; return, end
+          entry.start = EpochTT(varData(1));
+          entry.stop = EpochTT(varData(end));
+          % Add to cache
           entryTmp.start = entry.start; entryTmp.stop = entry.stop;
           entryTmp.vars = info.Variables;
           obj.cache.add_entry(entry.name, entryTmp);
@@ -306,33 +313,33 @@ function add2list_sci(name,curDir)
 
       temp       = strsplit(C{3}, '-');
       instrument = temp{1};
-      dbRoot     = obj.dbRoot;
+      dbRootDir  = obj.dbRoot;
 
       if strcmp(instrument, 'rpw')
         %==============================
         % CASE: Searching for RPW data
         %==============================
-        if exist(fullfile(dbRoot, 'latest'), 'dir')
+        if exist(fullfile(dbRootDir, 'latest'), 'dir')
           % CASE: obj.dbRoot has subdirectory "latest/".
           %       ==> Use RPW BIAS data (L2, L3) processed at IRFU.
           %
           % Ex: obj.dbRoot == /data/solo/data_irfu/
           %               ==> /data/solo/data_irfu/latest/rpw/
 
-          rDir = fullfile(dbRoot, 'latest', 'rpw');
+          rDir = fullfile(dbRootDir, 'latest', 'rpw');
         else
           % CASE: obj.dbRoot DOES NOT have subdirectory "latest/".
           %       ==> Use RPW data (all subsystems) mirrored from ROC/LESIA.
           %
           % Ex: obj.dbRoot == /data/solo/
           %               ==> /data/solo/remote/data/
-          rDir = fullfile(dbRoot, 'remote', 'data');
+          rDir = fullfile(dbRootDir, 'remote', 'data');
         end
       else
         %==================================
         % CASE: Searching for non-RPW data
         %==================================
-        rDir = fullfile(dbRoot, 'soar', instrument);
+        rDir = fullfile(dbRootDir, 'soar', instrument);
         if exist(rDir, 'dir')
           % CASE: obj.dbRoot has subdirectory "soar".
           %       ==> Use (presumed) SOAR mirror.
@@ -342,7 +349,7 @@ function add2list_sci(name,curDir)
           return
         end
 
-        rDir = fullfile(dbRoot, instrument);
+        rDir = fullfile(dbRootDir, instrument);
         if exist(rDir, 'dir')
           % CASE: obj.dbRoot has subdirectory named after instrument.
           %       ==> obj.dbRoot is a general folder for (multiple) non-RPW