Weak! I have lunged way further than that. I would've hit the guy with the shotty which I dislike way more than commando. Shotguns make rushing and getting high killstreaks impossible.
it really wasnt that long though. he kind of teleports twice. you see him go forward, then pause very quickly and then commando lunge. he was probably lagging and then commandoed...
there's a video on youtube from a machinima director who compares the distances between normal knife hit and commande knife hit.
the diffirence is really not that big, the most part of the visual "commando-launching" is due to ping...
i even do tht lunging thing without commando but obviously i stab further with commando but i only use commando for rushing so i dont die but wen knifers use it it annoys me