Just curious, whats your basis on this? I'm not disputing you or anything, it's just I've talked to people who've trained with Tamden, and they tell me the kid has extremely strong wrestling at 170lbs with decent submission skills, and has damn good boxing. I haven't seen anything on the kid, but still would be interested to hear your point of view of him.
He was getting pretty much embarassed by Spratt in most facets of the game before Pete...well, pulled a Pete Spratt. I don't remember seeing anything special from him aside from being ridiculously tall for welterweight. Also, Gono's dropping down and actually fighting guys closer to his size (weight-wise) then he has been for most of his career, which should work in his favor.
Though, in addition to the new rules and cage to deal with, American scoring is not going to look kindly on a guy who's known to steal fights in the last 5 minutes of a match.