Hi,
from what little I understand of bladders :-[ - I believe you can regularly TUR without major problems, as long as you can do the meat welding and they heal properly before the next R.
The inner surface of the bladder is fairly resiliant and quite thick - steadily renewing itself.

At times. when on screen, I have noticed small areas of the bladder surface and asked if that is cancerous and the consultant has not just said but shown that these 'bits' are just dead skin which he mechanically pulls away, as the bladder constantly regenerates.

Do bear in mind that it functions in a pretty hostile environment with a steady flow, giving endless expansion and contraction, as it fills and voids with Uric Acid! 8-)
The more interesting point about the bladder is how little they know about the brain's control of the bladder! :

Much of incontinnence is a breakdown of the brain's control over the sphincture at the neck of the bladder. I understand they have little understanding of the nerve patern for bladder messages. :-/
There is no clear reason why we do not wander around dribbling urine like rodents as the muscles of our bladder SEEM to be automatic, yet are easily disrupted :o - my wife had an idiot doing a laparoscopy puncture and badly repair her bladder without telling her and covering himself by making no entry on her notes! >

This has led to a hugely reduced capacity and also bladder urgency :-[ - it was only by noticing scar tissue during a flexi that we ever discovered the damage.

Sadly it seems progressive and there is no proof to come back at the incompetent fool who did the damage in the first place! :'(
Bladders all too frequently seem to develope a mind of their own! >

:-/ However regular minor TURs seem not to be too much of a problem.
I'm kind of hoping for at least 20 years of TURs

- in fact my medical file at the Urology Department is about 3" thick and I've promised to buy a case of Champagne if they can keep it going long enough to need its own filing cabinet draw ;D
Regards,
Greg L-W.