Thanks for the reply Thad. Here is how I'd address your points:
1."First of all, you?d have to come up with a scoring system that everyone agreed with. Good luck on that."
If the point system is based on analysis of games played without points and fine tuned as needed, why wouldn't most if not all players agree that it was an accurate representation? People wouldn't HAVE to play for points, but those who wanted to play in tournaments set up using points would know going in that that was how the tournament was set up, just as now players know that they will be playing using tournament rules. If a player objects to the way the tournament is run, s/he can always create his/her own.
2."Second, and more importantly, a win is a win. It doesn?t matter whether my opponent caps four of my pairs or none, as long as I get the five in a row (or five pairs). Also, if I resign a game, how would you score it? The only game I can think of that uses a points system to determine a champ is Div. I college football, and everyone agrees that?s a messed up system"
A win is still a win using the points system; however, using points you can evaluate the relative strenghts of the competitors more easily for the purpose of ratings and handicaps. Currently, if I thrash on a player, totally dominate the game as white it is exactly as you say, just a win. If that player barely manages to win against me as white, again a win is a win and we are now tied and have the same rank. So how do we determine who is the better player? Duplicate bridge uses points to determine winners. The point system used for college football is totally different from what I'm talking about here, so although everyone may agree that it is a totally messed up system it doesn't really affect the strength of my case one way or another. What if you resigned a game? Then,if you were playing for points you would get the number of points which you had accumulated in the game before resigning and your opponent would get his/hers. This would be incentive not to resign, because you would be playing a match, not just a game, and every point you could get might make a difference to the outcome.
3."Also, if Pente were played under a points system, we?d be less inclined to try out new lines."
This is probably true, for most players as I mentioned in my post- arguments against the system. However, my guess is that right now most players don't have much incentive to try out new lines(why risk a loss when you know how to win?), and therefore when they do most of them are following the trailblazers. If we make the game more attractive to new players (handicaping)we will have more potential trailblazers. Points might actually give incentive to explore new lines: can I find a better line where I win more quickly or capture more pairs in winning?
4."Also, if points were awarded for caps and length (shortness) of a game, would it be better to take an unnecessary cap. It would get me an extra pair (and thus more points), but make the game longer, and make me look like a weaker player."
I thought of this downside after posting, and here is how I'd resolve it. A player on the losing end of a game could prevent score padding by pointing out that the winner was trying to pad the score as soon as s/he noticed that that was occurring i.e.- you have an open three. Why didn't you make an open four this turn. The winner would be required to take the shortest line to a win once it was pointed out to him/her.