After Top Gear went off the air the first time, Midlands TV (IIRC) started a show called Fifth Gear of basically the same format. In fact, I think a clip from the show was posted here not that long ago. (About a car crashing at 120mph, again, IIRC.)
Anyway, what made the show we're the three personalities. And in doing so the BBC had captured lightening in a bottle. Yet, the problem is that you have lightening in said bottle. You can't keep it in there forever, and when a key part of your show is having a brash, offensive personality as part of that lightening, well, at some point it will get loose.
Although, I did chuckle at the "slope" double entrendre story. Seriously?!?!? 7+ million viewers and they got TWO complaints.