Does optirun disable vsync?

It's possible. I've googled a lot for it but no luck.

The reason I ask is that 60fps sounds like vsync to me.
The wildly variable rate w/ optirun sounds like no vsync.

No vsync could easily lead to tearing.
Hedgewars is not the sort of game that should benefit from 120fps and whatnot.

Assuming you could attain it... Perhaps you need to adjust your setup, since 75fps is awfully low. When I disable vsync and game frame rate limits, I can approach the max of 1000fps imposed by the game on my GeForce 9800T under linux. Something like 975fps. This is of course a waste of cpu, but useful when measuring perf tweaks.

Turnes out optirun was fail idea from the begining at the design level. The new "cool" way to use bumblebee is primusrun which has a lot better performance with forced 60fps.

The end result is that "primusrun hedgewars" makes hedgewars working fine at exacly 60pfs. Since Intel has exacly the same quality with exacly the same fps there is no point to use nvidia at all. At least playing hedgewars will be more energy efficient

It's worth noting that KDE compositing causes screen tearing with all running methods.

Ah. Yeah, I often suggest people turn off compositing.
Regardless of OS, can help, but under linux there's the issue of a bunch of different unpredictible compositing effects people might be using, open source drivers that are still reverse-engineering the device or half-assed binary drivers from manufacturers, and, well, as the mozilla guys can attest, the sorry state of xrender and support for it.

Not too sure why you're wrapping hedgewars. Should run fine w/o launching it from something else.
But, whatev *shrug*

That's exacly how this case ended. There is no benefit of using primusrun for hedgewars. Intel handles it perfectly well. I was testing all off this because i thought screen tearing was intel fault but it was compositing all along.