Actually it's entirely possible. As long as 1. you don't deal any major damage to it in short period of time or 2. let it attack somewhat frequently (aka, let it swing and you DODGE it, reguires good timing and high speed which medic and zerker are suitable + low weapon weight) and you can kite it almost forever. In other words, not really suitable for public games as someone will enrage it unless you're the sole survivor.
I've killed more than few with katana (and few times knife only, often causing many people to call me amusingly a hacker or so
) if I've had to solo 80+ specimen at once. In case if it rages, your only option is just to keep running, take it up the arse, take some steps back and start repeating the prodecure and probably heal whenever possible. If you don't attack it instantly after it smashes you, it doesn't rage again.
Of course the bad thing is if you have no clue what you're doing, you're going to get pounded quite fast enough and that if you have 2 FPs against you at once, then you might have a bit of trouble keeping them under control. And to clarfiy, I've tested the method on hard and suicidal even though on suicidal it reguires pretty damm good timing and skill to do it.