You're right that the players at the table understand the house rules in play and how those house rules alter the baseline expectation for D&D play.
See, right there, your characterization of what level you start the game at as a "house rule?" I don't get that at all. That's literally a foreign concept to me, and everyone I've ever played D&D with.
If your DM says that he's going to be running a game in the Forgotten Realms, do you call that a house rule too? If he says he's going to run the Age of Worms, is that a house rule?
Nagol said:
The baseline D&D ruleset offers indeterminate length play with known (and very substantial) power growth for successful play. A visitor to the game above, barring anyone informing him of the changes to the rules will come with an expectation that the campaign is of indeterminate length and with advancement. If a player was to inform him that the game is almost over because the characters are 3rd level, he will immediately recognise that as "not how D&D works" so house ruling must be in effect.
See, I understand all the words, its just the combination of them that makes no sense. There isn't any assumption of indeterminate length play. That's something that's entirely up to the group, not something that's "hard coded" into the game itself. Certainly it supports that kind of play, but not to the exclusion of other play styles, and not in such a way that it even implies that that's the way its supposed to play.
I think your conflating your experience with that game with something that's inherent within the game.
Nagol said:
And I do not. I see the level system as a character/player reward mechanism composed of massive change in character capability designed to promote continuous adventuring. If I want to play a game with a more static power curve at a preferred level of ability then I reach for a game that offers that form of game play.

But D&D does offer that. You just have to use it that way. You don't even need to really house rule it, you just use a certain subset of what's there.
1) Much shorter than today's novels - You can stack up several of the Fafhrd and Grey Mouser books together, and still not have as much content as a typical genre novel of today. We can argue over the quality of that content, but the note is still there.
Yes, but I'm not sure how relevent that is to a D&D campaign. Even an extremely long D&D campaign is going to struggle to have more content that, say, all the Conan stories, in spite of the fact that there's a fairly limited number of them and their all short.
Umbran said:
2) Most of those classics listed above are more episodic than later series. Fafhrd and Grey Mouser don't advance. But then again, the plot of their early stories hardly impinges on the later ones. You don't really need to read the first few to enjoy the latter ones.
In other words, they're more like D&D then? Especially the iconic "run out of a published module" type D&D?