Juan, you don't like hubbub b's sandwiched together. OK. Taste is indisputable. But what about: bubble, Hubble, nobbin... other double b's? Is it just the hubbub double-b because of the proximity of the u's? Too bad there's not a word bubbub! It would be a palindrome both front and back and inside-out!

Probably because, to me, the center bs in hub-bub are two distinct bs, while, in the other examples, the bs are more like a rolling-together sound...(interestingly enough, "roll together" didn't quite capture the effect I was trying to communicate, and when I changed it to "rolling-together" it was a much more effective image...but without the hyphen, "rolling together" wouldn't have been as effective either!).

I think this is where Musick's Dictum comes in somewhere, isn't it?