Heracles often completed his labors through his ingenuity rather than his great strength. Goliath’s great physical stature and strength didn’t prevent him from being defeated by a confident youngster. (And the story kind of loses its power if you read it as David just being lucky—rolling a critical hit.)
You see this kind of thing in comic books all the time. While the Fantastic Four have truly fantastic abilities, Lee and Kirby felt the need to create an enemy of cosmic proportions to pit them against. An enemy against whom their abilities meant very little.
While I can enjoy the numbers game part of role-playing games, I don’t think it’s crucial. (For me.) Ideally, I don’t think it’s the characters stats that should determine success but how the character is played. I suppose this is what we call “challenging the player” rather than “challenging the character”.
(Of course, it’s not an all-or-nothing affair. If the player is really “role playing”, then I suppose the two merge into “challenging the character as played by the player”. A player can play a character in a way that plays to their statistical advantages and minimizes their disadvantages. But I don’t think that makes much different to the point I’m trying to understand.)
During my Lord of the Rings campaign, I ran a solo play-by-e-mail bit for one of the players (Jax) whose character was doing some scouting alone. Never rolled a die. In the classic Traveller and Basic/Expert D&D games I ran, I tended to downplay the important of stats.
(Then there’s the whole stat advancement thing. If stats are downplayed, then isn’t stat advancement as well?)