Power up offensive Snorlax?

I powered up my offensive (Lick/HB) Snorlax, also 84%, all the way to 3255 CP. He's a truck, can take down whole waves of gyms sometimes.

I'd say yes, as this is arguably the highest DPS moveset.

CP isn't so important for an offensive pokemon unless it is something like alakazam or gengar, because of their low hp. In snorlax case, cp don't really matter, unless it is bellow 1700, something like that. If you can dodge and release the hyper beam in the right time, you will be able to defeat pretty much everyone with a 1800 snorlax. My better one is a 11/11/11 lick/HB with 1942, I can use him without big trouble against anything until 3000 cp (if it is not a snorlax, the time will probably not be enough).

Hard to answer this in a vacuum. This moveset is a killer combo for an attacking Snorlax. But without knowing what your attacking roster and your defensive rosters are, hard to advise. A 84% Snorlax is great regardless and you can use it as a defender if all else fails.

Personally, I like using my Snorlax for defensive purposes and save the lower CP ones for prestiging; mostly because I have a great attacking squad already and Snorlax candy are so hard to get.

I find Snorlax effective as an attacker but annoyingly slow so tend to use him as defender even with lick/body. Even with an 'attacking' moveset he makes a decent tanky defender.

Any moveset for Snorlax will make a great defender due to his high defence and HP stats so I would say IV is more important for Snorlax over moveset. 84% is good so I would power it up. It will be good for both offence and defence.