skid patches - yes number of places, this chart assumes you always skid with same foot forward, if you skid both ways you double the patches. Also note that the size of the patch can be spread if you don't hold a tight locked position, I find that a patch is about 1/8th of a tire circumference, but probably most biased in the center section of that 1/8th. Also note that skidding is not a must do slowing method, hard resistance (and front brake use) work too. I wore out a rear tire in 1mo. - mainly havin fun, now I don't skid anymore to save my new tires. You can also rotate tire on rim or chain on cog to move patches around

Point of all the above is not to think/worry too much about skid patches, but just to be more conciensous of them if you skid a lot and have 1 or 2 patches by chart above.

Al