Quite interesting,marlowe!
I was trying (and still do) to talk my friend in to writing a code for 16f processor to compute delayed signals however there was a problem with acuracy.The higher rpm the less acurate software calculates the delay however he ensured me that it still will work. Eventually i got the schematic and code written but i got too much on my hands now ,simply have no time to solder the board and burn the hex. Then i'll have to test.
Anyhow,keep us posted.Thats quite interesting topic!!At least to me!.
Take care and thanks.

Mitty