ply n repeats each event in a pattern n times within the event's original time slot

In MiniTidal, ply n pat repeats each event in the pattern n times within the slot it occupies — so a single hit becomes a burst of n evenly-spaced hits in the same time budget. It differs from fast: fast 2 $ s "bd sn" speeds up the whole pattern; ply 3 $ s "bd ~ sn cp" triples each individual hit in place, leaving the rests untouched. The effect is a stutter/roll on the notes while preserving the pattern’s skeleton.

Examples

ply 3 $ s "bd ~ sn cp"     -- each of bd, sn, cp becomes 3 rapid hits
ply 3 $ s "bd*4"           -- 12 hits per cycle

Assessment

Predict the number of audible hits per cycle produced by ply 2 $ s "bd ~ ~ sn" and describe their timing.