I did all that. you need to re-read. just coz nothing has happen in history doesn't preclude it from happening. you're part of the crew who said kikuyu-kalenjin alliance just after PEV was never gonna happen. You should try to rationalize your own bias more.
GEMA are not going to back any gema upstart without any realistic chance of winning. Uhuru without backing of Ruto (in 2013 ) or Moi (2002) was not going far. The same with Kibaki or Matiba (only strong gema candidate the last 30yrs). The next GEMA who wants PORK in 2022 is already late...he should be out there...working some alliance.
GEMA vote in 2022..that is combined kikuyu, meru and embu...will be about 20%. That is not enough to win nothing. We will know for sure in 2019 census...but going by 17.5% of 2009...and well know fact that they are transitioning to having less and less kids...you're looking at 15-16%...or about the same size with Kalenjin and Luhyas then. The baby boom is happening is pastoral communities...with maasai, turkana and somalis grew at 7-10% - and slowly they are going to turn 18.
You need to rationalize your confirmation bias. You might be right. But there is nothing in history that suggests you are.