Consider this: by halving the turn time compared to the standard turn time set in the rules for a competitive match, you're setting a very small base time reserve. If you set the base time reserve to 20+ minutes, you can easily play a +4+1 competitive match.
My reasoning: the timer will be a factor, but it won't be the primary influence on the outcome.
I understand that this tournament was conceived as a "game on someone else's territory"?