I'm not clear on why thith puththle took tho long. The theme'th thtraightforward... Yeah, that's quite enough of that, thank you very much. Apparently, actually, the theme is not exactly lisped phrases with funny results, because there are un-lisped Ss in two of the long theme answers. So let's just say it's replacing the initial S with a TH. And we thmile at the result.
THIGHSOFRELIEF wins, hands down. That's guffaw worthy. THUMBEROLYMPICS wins for most concise and ludicrous clue ("Quadrennial competition for hitchhikers?"). I don't get why 53A needed a TV critic in there. And then we get two bonus theme answers split between 1A/68A and 9A/66A. Neither one does much for me.
61 squares of theme, and a peculiarly constrained grid with essentially eight mini-puzzles separated by little in the way of entry material made for a slow moving experience. It's unfortunate when you have more than one flanged piece of construction material in a grid, especially when HBAR crosses HBOMB. There's a fair amount of abbreviations, a partial, a roman numeral, and a completely obscure biblical name (OMRI?!). In addition, HOO is uncalled for, and EMAG is a personal bete noire. Is AOL still a "web giant"?
On the plus side, I liked how BET followed ONECARD in the clues and the grid. 67A: Something that has low stakes? (TENT) is amusing. 27D: Features of many bras (CCUPS) was unexpected; how many entered "CliPS"?
A lot of not much in the fill. Does the theme make up for it? Nearly but not quite in my book.