I was rereading the book Littlewood's Miscellany and this passage struck me:
It used to be said that the discipline in 'manipulative skill' bore later fruit in original work. I should deny this almost absolutely - such skill is very short-winded. My actual experience has been that after a few years nothing remained to show for it all except the knack, which has lasted, of throwing off a set of (modern) Tripos questions both suitable and with the silly little touch of distinction we still feel is called for; this never bothers me as it does my juniors. (I said 'almost' absolutely; there could be rare exceptions. If Herman had been put on to some of the more elusive elementary inequalities at the right moment I can imagine his anticipating some of the latest and slickest proofs, perhaps even making new discoveries.)
I would like to ask a question to former math olympiad students who now are actively involved in math research. Do you find the training for olympiads useful in later research career as a mathematician?