Yes, chess masters at the top actually have groups of coaches (if they're preparing for an important match). Sometimes up to 5-10 people. Though it might not be so much coaches as "preparation team" - one of them might be the lead coach, one responsible for openings, one responsible for mental game, etc etc.
Novel writing is more subjective - if it were a clearly competitive endeavor with objective rules, I'm sure that the top performers would have coaches as well.
Novel writing is more subjective - if it were a clearly competitive endeavor with objective rules, I'm sure that the top performers would have coaches as well.