While stumbling across Lucky Star episode 15 (26-second clip, from 8:51 - 9:17), I found that there was a scene where the characters were watching a quiz show, where one of the questions asked was on keigo:
Q:「行く」の謙{けん}譲{じょう}語{ご}はなんでしょうか。
A:正{せい}解{かい}は「参{まい}る」でした!
(The characters were all certain it was 伺{うかが}う, but they all agree with 参る later.)
Now, if I am not mistaken, 伺う is used when the act of going to a place involves the listener (eg. saying はい、うかがいます! to one's boss, when asked to go to him) and 参る is used when the movement is not related to the listener (eg. not the boss' company, country, home, etc.). I think both verbs are humble forms of 行く.
Why, then, is 参る preferred as an answer to 伺う? Is there a nuance I am missing here?