Note also that code of average architectural quality will require about 1 maintenance day per year per 80 LoC just by virtue (vice?) of existing. (Paul Graham: a full-time maintenance engineer can own 20,000 lines of code.)
This is true in my personal observation. I mostly wrote two pieces of software rougly 50,000 lines each, and it's my limit of manageability.
Will need splitting up and modularizing if it needs to get larger.
For me, I could learn git no problem, write wrapper scripts for some things, etc... But I'm not explaining it's idiosyncrasies to other people on my team.
Git is not wrong by itself, there's just an impedance mismatch between it's model and a usable interface model. For most purposes, the index should completely hidden.