Most merge issues can be avoided with proper architecture and planning. If your files are so large that you have multiple devs working in the same file at the same time on a regular basis, then it's probably time to get more modular.

I honestly hate Git compared to SVN. The Git tool seems technically better. However, the easier aspects of the tool seems to have promoted less planning, more stepping on each other's toes, and what I see as non-value added work (merges, rebaseing, retesting, etc).