Vacuum advance's only function is to increase timing at light cruise conditions to get slightly better gas mileage at said light cruise. using it for any other use such as idle quality shows a total lack of knowledge and tuning ability.
Tuning for performance cams is done with vacuum advance disconnected and plugged an by using lighter advance springs, changing advance slot length or a combination of the two.

later vacuum advance can be added to ported vacuum and tuned to try and improve light cruise fuel mileage.