I had an issue with a pullet that might have warranted a bath... but, I used scissors and baby oil instead.  I'll share the little story with you:  
I was going out to shoo the stragglers into the run so I could shut it up for the night. One of the Colombian Wyandottes was running around. She looked like she was trying to run away from a nest that was stuck to her butt, and she had a blue thing hanging off her leg. So, I decided to investigate. Yep, she was trying her darndest to run away from an unfurled roll of fly paper that was wrapped around one wing, around her butt and up across the other side, with the blue case of it dangling by one leg. There was all manner of hay and debris stuck to the fly paper. She was in a panic. I was not amused. Thank God for fish nets. Such a marvel for catching fly paper shrouded chickens. I caught her, and brought her in so we could perform the fly paper extraction without being swamped with mosquitoes. I opted to cut the fly paper off her. Where there were new pin feathers or short wing feathers involved, I used a bit of baby oil to dissolve the glue. I'm sure I'll be able to pick her out in the crowd!
Actually, the baby oil did a good job of dissolving the glue.