some people do a cycle eg - prop, test e and deca. then (cruise)for the same amount of time on 250mg/wk of test e, then do a cycle (blast) again, followed by a cruise. most blasts last 8-12 weeks depending on compounds.
personally iv done 16 weeks cycles b4 but never a cruise type situation. from what iv heard from the "older" crowd they seem to like the blast/cruise scenario.
i am going to try it in the future.
i know some guys that have done a full on cycle(blast) for 12 months followed by intense PCT with HCG at high doses, with no known il effects on their body or functions, in saying that im pretty sure most guys would say it would be madness.