This makes sense. I guess you really have to factor in a lot of things before offering a spot. I always saw spotting balls to be a huge factor especially in long races since they're constant and remain throughout the entire match, whereas in games, you can catch up and make it even, etc.
I'd call myself a B player; where I play in my college pool room we've got maybe a few Cs and mostly D+s and such, so I'd want to give enough weight where the match is fair; I didn't know how these things matched up. Interesting stuff.
Just tinker with the spot. Most people aren't really looking for "fair" games, they are always trying to get the edge over one another.
But, for a spot to be truly fair, you should have a lot of break even sessions. Or if they aren't break even, the games/races you play after you adjust the spot should be even.
Example: game is 9 ball. player X gives player Y the 8 ball. Player Y loses 3 sets. They adjust the spot to the 7 and 8 ball. Player Y wins 3 sets and is even. (now, don't let someone trap you and say "but we played all night and we're even) This is NOT an even spot likely. Now player X adjusts and gives only the 7 to player Y. The sets go back and forth, on any given day, one player wins a set or two.
This is an example of a fair handicap. In most pool rooms player X is going to argue for just the 8 and player Y is going to argue for the 7 and the 8, when in fact the fair spot is the 7, which neither player wants to do, because they break even a lot.
Depending on the gap in skill level I've also seen combination of games on the wire and balls spotted, but to do this you really need to be playing at a high A or open class speed.
I'd suggest making some stipulations. Such as: giving your opponent the 8 and agreeing once someone wins X amount of sets or games, you readjust. Stipulate either you will give them the 7 or X amount of games on the wire if you win, and you have to adjust to play even if you lose. The stipulation would be in play for every time someone gets ahead X number of sets or games with a given spot.
So if you give him X spot and win X number of sets, you adjust, if you win another X number of games with that spot, you adjust......etc etc
I won't play if someone isn't willing to continually adjust until we are playing back and forth. If they aren't willing to adjust the spot, they are obviously just looking for free money.