The shorter match times means you keep a higher pace. I was more active and engaged in more scrambles in the match that I won than I would normally would be in a tournament with longer matches.
Another factor was that there was around 40 minutes between my matches. At least it was supposed to be about 40 minutes between my matches, but it ended up being less. That's a good amount of time to recover, so even though I ended up going against a guy with a bye in the first round, I don't think that having a match before that was a huge factor in why I lost my second round match.
Other than the matches running behind I really liked the format of the tournament.
I will also say that the level of competition between blue and purple is pretty different. This was my first purple belt tournament, and my first IBJJF tournament. I felt somewhat good about winning my first match, but really annoyed by losing my second. The day after my bracket I was speaking to a fellow competitor that won his bracket the year before at blue belt and this year he lost his first match at purple. There's definitely a step up in competition.