Tommy's point, and I think it s a fair one, is that while SDC had an excellent freeroll, they didn't go from being a 2:12+ (2:14ish average 2001-2006) to a sub 2:05 team (2008-2009) on the downhill. SDC absolutely improved going down, but the real difference was going up the hills. Nothing I've seen shows that they were far ahead of the other top-tier teams when gravity was in charge. We can all agree that the buggy that wins, holds the record, etc. must be fast, but not necessarily the fastest ever or even fastest of that year.
To put it another way: from all indications, Bonsai's free roll put within striking distance of any credible times I've seen, both in practice and on race day. Both the big trophy and the "horse race for second" depends on pairing such a performance with a well trained (!) and talented push team. That and a bit of luck.