I think we assume too much when we are looking at other a/c in an air battle...it's very hard to judge Energy sometimes...and for that reason a/c seem faster than they are supposed to be. A slight nose down configuration will gain the con your chasing a little bit of extra speed...so it looks like for some reason it's capable of more than it's supposed to...or vice-versa the con catches you because he had more E than you thought.
That and there are some very capable pilots in these games. Guys with years of experience...they are going to surprise us all from time to time. They learn fuel loads, turn rates and handling issues of an a/c and they can exploit them.
Aces High is competative. We are all competative. We all want to win that 1 vs 1. Sometime we just get beat. S*** happens in an arena filled with bloodthirsty fighter planes!!! Shake it off and have fun...your day will come again as it always does and success will be yours again.
Have fun out there.