It is very very unlikely. Sure, maybe a couple guilds merge to create a superguild. But that would still not win many high diamond groupings in my world. I can tell you there are several guilds ranked above my guild that finished below us in the past 5 seasons when they were in our grouping. If you come in last against the high diamond (1000LP group), then move down to low-diamond or platinum and come in first - that moves you back up to the 1000 LP group - but this time with a victory under your belt. The team that can't compete in high diamond then moves down and comes back up will be ranked higher than the team that came in 2nd 3 times in a row against the high diamond group. Coming in 1st in platinum, then 8th in 1000LP, then 1st in Platinum is ranked way way higher than 2nd in 1000LP, 2nd in 1000LP, 2nd in 1000LP.