whenever you make a modification (suggestion here), add a comment to the file..
for me in .tpl (templates), i add {* SD:Mod - reason for modification *}
for php files, i add // SD:Mod - reason for modification
this allows for a utility like grep (free) to just search for any file with "SD:Mod" in it as a reminder.
of course Beyond Compare (not a free utility) will also note any differences as well..
it's just good to put in an indicator of sorts in any file that you touched it and for what reason and where.. :2cents: