To discuss a bit, I was wondering what were your favorite comedic scenes. I know it's hard to decide there are so many. I guess for me it's the toilet paper battle in Kyubei introduction arc. It's one of the moment where you think, Sorachi won't do that... and he does.
Ur right, Gintama is a-laugh-a-minute, but at the same time Sorachi very skillfully balances it with the occassional very meaningful/ extremely emo arcs...
(although, its been a looong time now since the Shitenou arc, and we're still waiting for the develoment of Kiheitai + 7th Division co-operation.. ><
Well, back on track, off the top of my head, id say i loved the whole "Heidi" parody from when Hasegawa was being sued for giving an unsuspecting woman a Kinniku Buster

That was all Awesome hahaha!
About the toilet paper thing, that was awesome too, but it just highlights a troublesome point- that without a pretty good knowledge of Japanese language and culture (and knowledge of many mangas), its impossible to 'get' all of Sorachi's wordplay and nuanced in-jokes..!! In the toilet paper scene, there was one part when he played on the fact that "Kami" can mean "God" and also "Paper", right?
