A very strange Question about my Cat

Question
I have three cats, Pacey (F) age 5, Shamus (M) Age 3 and Oliver (M) age 1. This question is about Shamus

Shamus is a mostly healthy cat, but has a level 4 heart murmur. We've had him since he was a kitten, and he always gets his shots. He's neutered, but the vet wasn't sure he would make it through (we got lucky).  He's a little bit overweight, however, weighing in at about 14 lbs (the vet figures he should be 11 or 12 ideally)

Ever since he's been young, Shamus has loved the water.  He would sleep in the wet sink, jump into the shower to join me, jump into the toilet (Yep!), and loves it when we leave the tap running so he can play in the water. We usually leave it running just a dribble, (although he prefers it at a steady stream, he just gets too soaking wet, shakes it off all over the place, and soaks the furniture). He drinks the running water (won't drink from a bowl of water), and lets it run all over his back, especially in one spot, which is normally soaking wet.  The spot is right on the part where his left front leg meets his body (his shoulder?) We usually turn the tap on for him 3-4 times a day until he finishes, which is about 5-10 minutes (he lets us know when he wants it by running at full tilt meowing into the bathroom)

Anyhow, he has done this since we've had him so we never thought it was a problem. Recently, however the spot that is typically wet has become bald. The hair kind of shrivelled and dried up and rubbed off.

Should we stop letting him play in the water altogether?  Cut back on his shower time? Give him a bath?  Rub him with moisturizer? Conditioner? Or is this maybe something completely unrelated to the water? I'm at a loss, because quite frankly this is the most bizarre cat behaviour I've ever seen. If you have any explanation for his bizarre behaviour, that would be interesting too... we've always just thought he was a little slower than most cats, but we love him anyway.

Thanks very much for your help...
I can take a picture of the spot if you think that might help.  

Answer
My guess is that he is over-grooming the spot from the continuous water on it.  I would stop the water play time for now and apply neosporin to the area and watch if any hair is growing back.  If the hair isn't growing back, then you should consult your veterinarian.