I've never run tests but I know from observation that hiding infantry with an arc will usually un-hide on their own initiative and start shooting/grenading etc if the enemy get real close (say around 20 metres or less), I suppose their instinct for self-preservation kicks in.
However occasionally somebody
won't un-hide and the enemy will get close enough to put a gun barrel in the back of his neck, that's the risk you take when giving hide orders..
As for advancing and reversing AFV's to trigger hiders, it might or might not work because the moving vehicle spots poorly and might not even see the grenade-thrower who killed him, so you lose a vehicle for nothing.
Personally I prefer loads of tank area-fire to flush out infantry, it works whether they're hiding or not because they begin wriggling around under area-fire and appear on the map and can be dealt with.
Hey, I hang at FGM a lot nowadays, look in sometime..:)
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