LOL, I think if you have a clip in one hand to reload and you hit your knife button, you should lose your ammo to knife. That way it makes your situational awareness a little better, "Hmmm, do I want to take cover, reload, re-engage, or... if he's hurt enough, maybe I can sprint up and knife him, or I can sit here and reload, I'll take the latter, OH [censored], here he comes, KNIFE, CRAP I NEED AMMO HELP!"
aNYways, I have no issues with knifing in this game, and it is the middle mouse button for me, I rarely use it but I have managed 2 kills with it when I've injured someone enough and notice them try to take cover. I also did a test on it however, and I just feel that the mechanics for the knife are fine, I have been able to pull it out any and every time I've hit the melee key, examples includes, pistols, machineguns, sub machineguns, I haven't tried the heavy weapons though, and testing took playing during switching, reloading, and firing.
Funny, I think Battlefield2 was my favorite FPS of all time, I even enjoy BFBC2, but now... the mother of them all is due for release this fall,

hopefully they stick to it, though I am patient, if there are bugs, please fix em first,

, though, I also don't mind playing through some bugs until they are resolved either, lmfao. I am patient and understanding.