I'm with King Funk on this one.
Lowering the timer isn't what will make the tournament run faster. Changing it would be likely to force floaties players who actually want to win the game by removing their opponent's stocks to change their strategy for a timeout win, and that shouldn't happen at all. I don't mind timeouts at all, but I think that if an player wants to get a "no stocks left" win, he should be have the right to do it. That's why in my opinion, the timer should be set at the lowest duration for which no "accidental" timeout happens. Six minutes is too low for that, especially on Dreamland, or Pokémon Stadium due to the transformations.
Also, I don't really see the point of lowering the timer. It will NOT make the tournament run faster, as 8-minute games are extremely rare. On the contrary, I suspect it would actually increase the average game duration, since timeout could become way easier to reach. This is only an hypothesis, and I'd like to know if some TOs were to try it.
Lowering stocks would be a much safer way to lower the event's duration, but I'm not too keen about it. I think that nealdt used it in 2007 or 2008 for Champ Combo, so you could ask him how efficient it was.