Tom Halsey
International Coach
According to this theory, Glenn McGrath in the latter part of his career isn't any different from 100s of club seamers in England. Except he didn't even swing it very much.Kumar appears to be no different from 100s of club seamers in England. Bowling standard medium pace outers should not, IMO, qualify for a Test place.
Ignore all the absolutist principles about what a Test bowler should or shouldn't do, a Test bowler should have an expected average of less than all the people he's fighting for his place with, taking into account conditions etc. Small sample though it is, Kumar has done well in his international career so far, and done well in his domestic career.