WEP should always be allowed. I do not like fights where you know everything about your opponent before you even get off the runway. It doesn't make the fight very fun or interesting. In the DA you know who you're fighting, what alt you will merge at, what plane they will be flying, what speed he will be at, and that he won't shoot on the merge. This really doesn't make for very interesting fights IMO. I think the most interesting and fun fights you will find are in the MA where you have no idea who you are fighting, what style of flying they fly, what alt they are at, what planes you'll meet, their E states, or if he's going to take HO shots. You know absolutely nothing about your opponent until you start to merge and figure it out as you go, and this element of the unknown makes fights far more interesting IMO.
Though I know the point of this Dueling Tourney is to Duel so rules have to be set.