It could be made so that a nickname is automatically selected per-page. This way threads he comments in could be followed. A small pool of 5 or so names could be reused so that he couldn't be exposed by finding the user that has just been created.
Example implementation:
unames=['bob1','bob2','pg']
lu=len(unames)
secret_seed=309580435
from binascii import crc32
def hash_eq(number):
return crc32(str(number),secret_seed)
def get_uname(page_id):
return unames[hash_eq(page_id)%lu]