I gave Gryff a bath, today, and lived to tell the tale.
Wow! That wasn't fun. But, his fur just had a dusty appearance and feel, and while he didn't 'stink' he definitely didn't smell clean. He objected strongly but I got it done with just one semi-significant ouchie and a couple of smaller ones. I wore two work shirts to protect my arms but am sadly lacking in any flexible Kevlar work gloves. I did a good antibacterial treatment so I should be fine, but I'll keep an eye on things.
He was pretty upset with me, for a while, but now he's back on my lap, looking much shinier, feeling much smoother and smelling much nicer. His snuggles will be even more appreciated, now.
I don't plan on ever doing THAT again!
= new reply since forum marked as read
Well 4.3 lb kitten. His meows were heartbreaking. But at the end of the day, it was a good decision to bathe him. And he's forgiven me. I hope. If you don't see any posts from me, tomorrow, you can figure he got his revenge. 
Someone should invent an enclosed contraption with an opening for their head, but the rest is contained and little jets of water/shampoo shoot out while little brushes massage the shampoo into their fur. Then you open the drain, and switch to sprays of clear, warm water to remove the shampoo, and that runs out of the open drain.
Or, maybe leather mittens to restrain their claws of death.
I never bathed Sophie until a few weeks before she died, but she had gotten some fleas and combing just wasn't doing the job. She struggled, a bit, but it went much better than I imagined it could. She looked and felt so much better, afterwards.
It is very sweet of you to care for all these kitties 
.
In their own way you can be sure they appreciate it...