Then again, in 1e xp is to be given for an avoided encounter just as if it was a defeated encounter, so (if followed to the letter) talking to former dungeon delvers etc. and learning what to avoid would in fact get you the xp once you went into that adventure and duly avoided it. This is one thing I think later D&D versions would do well to include* and-or more greatly emphasize in order to give stealth parties their due; and as a side-effect point to there being ways to approach an adventure that don't start and end with all guns blazing.
* - maybe not word for word, but some sort of variant that rewards for encounter avoidance on a par with encounter defeat.
I think to be perfectly honest EGG understood and based on what [MENTION=42582]pemerton[/MENTION] has dug out of DMG and PHB he had SOME SORT of process he went through, but he surely didn't explain it in any coherent way that could be closely reproduced. No doubt we all 'figured it out', so it wasn't really some crippling issue. It was just par for the course with 1e, you pretty much had to write the rules yourself based on tradition and the various obscure passages in the books. lol. I ran 1e and 2e for 15 or more years, so I don't even feel like its a burden at this point, but after running 4e I don't want to go back.
If you look through some of the classic 1e adventures there's boatloads of treasure just waiting to be found; for example a small-ish party of 4 to 6 characters could very easily come back from A-2 Slavers' Stockade with a treasury good for each of 'em clearing 40K g.p. or more as their share, assuming roughly DMG prices for magic items.
Training costs are a nice way to drain some of it. You're being a bit harsh though, if you're charging a root 1500 x (level squared) before DM adjustments. According to the 1e DMG it's a more linear 1500 x level per week, where the length of time in weeks is a result of the DM adjustments for good play etc. which makes it kinda random. (personally, I've never used the DM adjustment part)
Well, I'm just reading what it says in the books. Every time you go up a level you must train for a number of weeks equal to the new level x a DM determined 'RP factor' from 1 to 4. You must hire an expert of at least the new level to train you, and that expert will charge 1,500gp per week. That means the minimum price for reaching level 6 is 9,000gp, and if you have an 'RP factor' that isn't 1.0 (Perfect RP, player always acts in character and never meta-games in any avoidable way, players to his class-specific goals at all times, etc) then its somewhere north of that. So your hypothetical A-2 character gets 40k g.p. (which honestly seems a little high, but I'm not about to go unpack A2 and read it to see what's in it) then at least 10k of that is going to training. That would definitely leave a huge haul. All I can say is no AD&D 1e character of mine ever accumulated anything like that kind of wealth at that level. I even remember playing through that series of modules. We ended up around 8th level after A4 I think, but you also lose ALL of your possessions in that module, and definitely don't end up with even a copper piece (though you might have stashed some money or be able to go back and acquire some by revisiting some of the earlier locations).
The game says that only if you want to read it that way; never mind that even just what you've written there could represent full-time job description.

The lack of mechanics is a feature to me, as it means I don't have to think about them.
Well, that's what I'm saying. The game isn't providing anything for you. We can all have fun with whatever, why does the game provide rules for magic? I mean I could just equally say it should be free-form and that would be better.
What I'm finding as we get into higher levels* (beyond about 9th-ish) is that the front-liners are becoming more useful (and necessary!) again largely because there's so many situations arising where spells don't always help much; be it null- or wild-magic zones, adventuring off-plane where magic goes screwy and-or spells cannot be recovered, foes with high magic resistance or outright immunity, and so forth.
* - I currently play in one game of levels 8th-10th, another (part-time) of 9th-11th, and DM one of 6th-10th, all 1e-based.
There is, to be sure, a run between about 5th and 8th where the casters have their day, no doubt of that.
Lanefan
Yeah, I don't know. My experience in 1e/2e was that much past 9th level you better be a spell caster if you wanted to really make any impact. Our parties were pretty much all-caster and defended by a series of items and enchantments that were designed to minimize any chance of these kinds of things happening.
If we were fighting something with magic resistance for instance then we did so by 'indirect attack' (collapse the room with Rock to Mud for example) which isn't bothered by MR (nor does it allow for saves, generally). We would also play in a 'total war' mode. OK, there's a dungeon containing a lich. We're not friggin going in after that bastard! Are you crazy? 6 months of passwalls, excavation, dig spells, etc and Mr Lich's hideaway is no longer so hidey! (I mean I'm just making up an example, but this was the sort of things we did). Obviously sometimes you just gotta dive in, but carefully, systematic, and very Clausewitzian approaches to dealing with our problems were the norm. We always had backup plans, contingencies, drills for different scenarios, etc. Once we went into a place it was like a NASA Moon Shot, every phase was mapped out, planned, spell load-outs were built around it, scrolls were penned, exact tactics executed, and if things weren't right, screw it we'd just pull out and make another plan.
In that environment casting was so premium that the most we would ever do was maybe have a couple guys that were MC fighters, maybe a bard, something like that. You better have access to 5th level spells, or you were probably not pulling your weight.
I'm not saying our group was typical! Of course the main DM that I played with amped up the opposition to preposterous levels in the end. One of our operations was penetrating a CITY filled with 1000's of beholders. The nasty MM kind. We never did really root out that place, it was just impossible. Still, we made multiple forays and figured out ways to defeat waves of beholders at a time, which was no small feat (it was expensive too as I recall, the bastards were always disintegrating expensive equipment!).