TW matchmaking has been terrible for quite some time. We just went up against a guild with 12.3M average GP. We have 9.9M average GP. Their record the last 3 months is 14-0. Their record the last 6 months is 23-3. We are closer to a .500 record. Our two guilds should not have been going up against each other. Looking at their active GP over the past few months, they are clearly sandbagging.
Matchmaking supposedly takes into account the last two matches. Just increase that to 10 or even 5 and maybe there would be more balanced matches. Or use a system closer to GAC. Give these almost undefeated guilds a challenge every now and then.