Training To Level Up Is Unnecessary And Doesn't Make Sense

Apparently in 1st Edition Advanced Dungeons & Dragons, when you accrued enough XP to level up, you didn't. At least not right away, and in many cases not without for some reason having to pay a trainer. 

The DM was supposed to grade your performance every adventure: Excellent (1), Superior (2), Fair (3), and Poor (4). When you would level up, you took all of your ratings and divided them by the number of adventures to get something between 1 and 4 (which could include decimals, and the book told you to note them because each day was worth 0.145).

This result was the number of weeks needed to train in order to level up, and it cost you anywhere from 1,500 to 6,000 gold pieces per level, per week. If you managed to get less than a 2 on your final grade, you could arbitrarily waive the training fee, but it took twice as long. Got a 2 or higher? Whelp, if you can't afford the fee, you're level-locked until you pony up the cash.

It's absurd to think that a fighter could go into a catacomb, risk his life destroying a bunch of skeletons, zombies, perhaps a ghoul or two, stagger back to town with some loot, and regardless of how much experience he's earned in the process actually fighting monsters, still have to pay some random NPC an absurd amount of money to see any sort of improvement at all over the course of weeks.

And what is the fighter doing during this time? Sparring with the NPC, who isn't really trying to kill him. Hitting practice dummies? Target practice?

This sounds like the sort of activities he would have engaged in prior to becoming a fighter, so how does that make him better? At least, any better than fighting for his life against opponents that actually were trying to kill him. And why does it arbitrarily have to be some drastically overpaid NPC? Why can't two fighter PCs just practice with each other?

In a similar vein, I'm wondering what the wizard is doing the whole time. Gotta be something besides casting spells, because he could do that anywhere, anytime, for free. And again, it's not even always necessary: you can get away without a trainer, just gotta have good grades from your DM.

2nd Edition at the least had the sense to make this procedure optional--as well as reducing the cost and necessary time--and it was wisely abandoned in subsequent editions, but this got me thinking: instead of going out into the world, getting XP doing things, then having to pay someone in order to benefit from it, why not have that training translate into XP gained?

You could do it by yourself, but having a trainer whose level/HD is at least higher than your own increases the amount. Something to do during a downtime period, and in this manner you could essentially convert unwanted/unnecessary cash to XP (which actually makes sense, unlike older editions where you automatically received XP by finding loot for some reason).  

I think the rate should start at a set amount, reduced by your level (rote practice becomes less beneficial the more experienced you are), which can be offset by having a trainer. The cash amount would depend entirely on the trainer's level/HD, because there's no way he knows how high level you are.

The trick is to make it worthwhile, otherwise players won't bother. After all, in Dungeons & Delvers there are plenty of mundane-or-nearly-so items for the characters to make themselves (which all require their own tools, supplies, and/or facilities to craft). That's something I'll need to think about. Do some math. See what the wife and kids will be willing to pay.

But then this isn't an actual issue, something that needs solving. It's just something I thought of while pondering the absurdity of having to train in order to level up despite sufficient real-world experience. If I can't make it work? Eh, no biggie. I think it would be neat, give characters something to do if a wizard is taking a bunch of time researching spells or something, and a training facility could be part of a stronghold, which would be another reason for characters to invest in one.