You should wait to hear from those more experienced, but from my research and limited experience there really is not a maximum number of baths. I've had my boy for almost a month now and I give him a
bath daily because he really enjoys it and my wife has a little OCD and loves handling him. The baths are not very long, sometimes just 5 minutes, but I've showed him how to "shower" under the sink faucet and he loves it, always lunging his head up and into the falling warm water. He does this while I cup him in my hand and let the water fill a bit. This started after I put him in a tuperware container and used a miniature spoon to poor water over his head and body. He closed his eyes all the time and reached up for the water with his head, lol, so I got him used to the more powerful and consistent faucet.
Anyway, he just finished shedding, so for the past 3 days I bathed him twice a day just to help with the shed. He shed his entire body, except for the tail, in one day. Pretty awesome. I think the baths helped with that. He looks amazing, and is super healthy.
There is the debate whether or not dragons take in water from the rear--this used to be common knowledge, but has been challenged more recently. So if they do,
bathing too much could theoretically over-
hydrate them, but you'd need some serious
hydrating to get there, i think. I say this because I fed my boy reptiworms for a few days when I ran out of crickets, and they are super moist, resulting in runny poop and lots of water with it. Their poop is awesome as is, very little and easy to clean; with extra
hydration, water comes with the poop and makes a much worse mess. So if they do take on too much water, they just release it. The main concern is fluid in the lungs, which is why proper humidity is vital. This is also why I don't have him near water for too long--humidity is always higher near water.
My guy prefers to poop on a paper towel. Since he's a kid he'll still poop pretty much wherever he wants--the
bath, his driftwood, me or my wife, etc--but he does prefer the towel as he can drag his butt like a dog and wipe after duty calls. When I offer this to him, he usually uses it, but you have to feed consistently (same amount at same time every day) to make him poop consistently. When you do this, you'll see the time and know when your buddie will poop. Then, move him to a towel or something and voila, poop. I think they learn these behaviors quickly if you are consistent. Next time he poops on you just clean up and bring him back. I doubt he'll have enough poop for another assault, and you'll start to teach him something other than: "when I hold you, poop on me and then I'll leave you alone." But taking him out just once a month is like prison, IMO. Please spend more time with him, or just give him some roam time in a safe area. If I neglect my boy for more than 2 hrs he starts looking at me funny and gets excited every time I walk pass his tank. Animals learn through behavior. You can't leave him in a static environment and expect him to just figure something out or have some realization. You need to teach him, provide him with experiences that will create opportunities for him to learn, like potty training. Be active, spend time with him DAILY, and he will respond.
