Yes Grenades/Smoke Grenades/Chemlights can pass through window without breaking the glass or bouncing of it. Tested on Airport Control Tower, Barracks(New), House(Big), House(Large), Bungalow...

And another problem with Airport Control Tower is that you can see glass particles when you shoot through broken glass.

Game version: Beta 0.71.106777 - development branch.

OK Here are the results

TEST 1 - Netbook(28-30 FPS, FRAPS):
Ammo start: 5000
Ammo end: 3240
Test duration: 60 seconds
Calculated Rate of Fire: 1760 rpm

TEST 2 - Desktop(57-58 FPS, FRAPS):
Ammo start: 5000
Ammo end: 1464
Test duration: 60 seconds
Calculated Rate of Fire: 3536 rpm

Game version: Beta 0.71.106777 - development branch.

UPDATE: Added calculated rate of fire.
UPDATE2: Both tests are based on in-game stopwatch too.

BLUFOR is NATO in Arma 3 and NATO isn't IDF.

(ARMA 3 is set in the near-future, during the mid-2030s, where NATO forces deployed in the Greek islands of the Aegean Sea are trying to hold off a massive Iranian military offensive from the east.)

Try test in EDITOR not in multiplayer where client performance depends on server performance