I do, and since I am the only one that matters the answer is E) 100%.
(At least I'm honest.)
I don't think it's ridiculously large - like catvomit, I'm really great, therefore it is indeed totally fitting that my ego is large.
That is a difficult question. One that I feel compelled to answer rather than addressing the pressing scientific proposal-related questions on my to-do list tonight (they can wait)... By "ego", I assume you mean Freud's ego. According to Freud the ego seeks to please the id’s drive in realistic ways that will benefit in the long term rather than bring grief. Chess is, in many ways, antithetical to this drive in that suffering, loss and grief are endemic to the game. Mistakes, blunders and errors are the driving force of chess and one is always struggling for a higher ranking. Those who are attracted to chess are seeking to prove themselves in this game of kings, what little ego we might try to scrape together can be easily torpedoed by a single game against a much higher ranked opponent. While many of us present a shell of the inflated ego, I suspect the opposite may indeed lie within...
A) 0%
B) 1%
C) 50%
D) 99%
E) 100%