You live in the bath? Doesn't that rather wrinkle your skin up? I do think that in the Book of English Eccentrics there was such a person, but I didn't know that this was prevelant in Scotland also. Doesn't the excessive use of hot water go somewhat against your misery principal? Or is the water cold? Either way I assume that you would have to change it from time to time, no?
The things that one learns of on Pianostreet 
I think that you have probably already heard of the city of Bath and know its location.
What living in that city does for one's skin is less of an issue than what it does for one's lungs at times, given that the proximity of seven hills around it (as with Rome but on a much smaller scale than the Italian capital) tends to ensure that the humidity is rather high here, regardless of temperature. My skin isn't wrinkled, anyway (although who knows what might be the dermatological side-effects of reading the frequently occurring God-never-forsaken content of our forum Goddess susanistimo's posts?).
I do not understand what you mean about a misery principal? - who is principal of what and why might misery be involved? - you'll need to explain this.
My attitude to bathing in cold water is analogous to the contemptuous one expressed by Delius and gleefully quoted by Sorabji in his book
Mi Contra Fa: "it's all this bloody English Jesus Christ business with a cold bath first thing in the morning".
Best,
Alistair