Q: git history isn’t very discoverable… How do I find the commit that removed the code I want back?
Please, don’t commit commented out code
Kent C. Dodds
21018

Also, when you want to keep track of the instances when you removed some major part. You can keep the message and reason to remove in commit comment(while you’re removing). This way it becomes easier to search in the log. For example-
A git user will do - git log | grep “my precious comment”
A svn user will do - svn log | grep “my precious comment”