First, someone did post a study that showed that alcohol does potentiate MDMA.
Second, my best roll ever was about my 30th or 40th time. And I think a large part of that was the preparation which included me getting 24ozs of a 10% beer, so I guess basically 4 glass of wine. I chugged half, waited 10 minutes or so, popped the pills, drove to the gas station that's 2 miles away, bought some suckers, came back home and finished the alcohol.
Wow. Blew me away. In fact, on the way to the store I could already feel some of the effects, and that was within 5 minutes of dropping (mind you, I let it dissolve under my tongue and I took 2 because I had been told they were weak), but I've never had it hit me that fast before. Not even close.
(Mind you, there were other parts to my prep, namely 1) not taking 5HTP prior (which I had usually done), 2) not eating for 6 or 7 hours, 3) taking a teaspoon or two of baking soda (no idea if there's any scientific evidence to support its use, but it's been theorized to keep the MDMA in your system longer.)