Unblocking on 'Thin Ice' basis
Sometimes, when a user asks to be unblocked after a six-month period, or if an issue has blown over, they will be unblocked, but on a 'thin ice' basis. Their contributions will be carefully monitored, and if any rules are broken, they will be re-blocked, possibly permanently dependent on the rule broken. After a year under these rules, the user will be able to 'climb off the thin ice'.
NOTE: Vandalism while on thin ice will result in an instant, permanent block with no chance of return.