(In reply to Nicolai H�hnle from comment #111)
> However, if I recall correctly, XCOM issues DrawRangeElements calls with
> ranges that are larger than necessary.

My understanding was that exactly the opposite was the issue - the game sends
indices outside of the specified bounds. Quoting Jose [1]:
"the application is giving a hint to the OpenGL driver that indices are between
0 and 215, but in fact in call 21933, the index at position 164 is 216, and
more later."
[1] https://github.com/apitrace/apitrace/issues/407#issuecomment-166619366