Darin told the story well. Thank you, Darin!
Sadly, the online page at http://www.stanpope.net/ppngen.html
and (I think) the DDL version that is included in GPRM, et.al., only support up to 6 lane tracks.
Since Cory Young is the "keeper of the code" for the DDL version, I'll have to let him give the final say on the DDL version capabilities... or, maybe, someone who has GPRM readily accessible on their computer!
A subtle value to the PPN approach for timed racing is that, absent errors in timing, there is a high correlation between "finish order" dependent results (points) and time ranking. This high correlation is a result of the nearly equal opponent mix that each racer faces. Since finish order can be "validated" by the audience, the audience can satisfy themselves that points results are reached accurately. If they can keep up with the points stats, then they can compare points ranking with time rankings and develop confidence in the time rankings. (As one whose district was bitten badly by timing errors by a supposedly experienced crew, I put a pretty high value on the audience being able to validate the official results from their own observations.)
Simple lane rotation, on the other hand, does not have a high correlation between ranking by heat points and ranking by heat times. Consequently, it is harder to show that timing is consistent throughout the races.
In between these extremes, a wide variety of chart generator vectors could be used which provide more balance in the competition than does simple lane rotation, but less balance than proper PPN. Even randomly produced generators (provided some simple criteria are adopted to exclude certain random choices) would do far better than simple lane rotation!
If you have consistent timing apparatus and well trained operators, then 8 times turned in for each racer in age-group prelims should be neither more nor less valid than eight times recorded by each participant in the finals. (To the extent that there is random variation in the times, then the times in the finals will moderate from their prelim results.) Even if there is no more validity, it is reassuring to see prelim times reaffirmed by times in the finals. The "clinker" in this is the pattern of run times as teh cars accumulate heats. Some degrade more rapidly than others, and the cars with "staying power" will tend to do better if there are finals than if their prelim times are compared.