Because the NSK doesn't want to see him become the weakest yokozuna among the four and have to retire him after a year or two. The NSK guys know clearly Geek's real strength.However, I wonder if the NSK can resist the pressure from the public's demanding of a Japan-born yokozuna.
On what basis or evidence do you make these claims?
Just look at Geek's last year's record (9, 8, 6, 8, 11 and 8 wins). He couldn't meet the minimal requirement (9-6) for an Ozeki ! At his current age of 31, do you believe he can improve? If Hakuho at 30 years' old is already going down slope, what about Geek?
8-7 every other basho is the minimal requirement for an Ozeki.
For promotion to Ozeki, a sanyaku rikishi needs average 11 wins in three consecutive basho. But once promoted, only a 8-7 every other basho is enough. Isn't it ridiculous?
Not really to be honest. Ōzeki is the second highest rank and should not be a revolving door. It should bring some additional benefits to the rikishi who manage to be promoted. And a "weak" Ōzeki can maintain his rank by going MK-KK-MK-KK for only so long. Eventually he will end up being demoted.