hey steve, I'm not sure if you are looking at just monitoring your own growth, or ranking as in A, B, C in organized competition. there are different ways to rank and/or assign handicaps. in MNSPA leagues I use 4 different systems
normally I don't use high runs at all in calculations. I know bob jewet wrote an interesting handicapping system. 14and1.com and one of my systems uses a W/L by how many points you win.
I think for tracking progress, high runs could be a negative. Maybe an average high run would give you a better idea, but there is a difference between having huge high runs and playing smart against a well versed opponent, especially at lower levels. Your BPI could be very low if you had a lot of safety wars, but tactically it was correct. I suppose a mix would be ideal of BPI, high run average, and win/loss.
i agree with creedo, usually the question is what's your high run, and i ask myself that when trying to place new players in a division for leagues/tourneys. You can see if someone is a novice or just starting out, or able to string multiple racks together
Matt