Rolls are mechanical devices to deliver a control signal to the
player mechanism.  That signal needs to be delivered at the right
speed.  This is the speed that matters, not the speed of the paper.

Some companies used perforators with a variety of punch sizes.
A critical aspect of rolls is the size of strengthening bridges.
To keep bridge size constant, changes in punch size require the
punch spacing to be adjusted: larger punches require greater spacing
than smaller punches.  Therefore, rolls cut with larger punches
need a higher paper speed, even though cut from precisely the same
master file.

Ampico adopted relatively large punches, 0.078" diameter, some time
into production and therefore had to increase all their marked roll
tempos.  Aeolian operated a variety of perforators and some rolls are
known to exist in three differing tempo markings.  And some notably
long rolls were compressed in later years by cutting with reduced
step sizes.

Welte cut their original T100 rolls with larger punches than the later
T98, so the later rolls run at a slower (fixed) tempo.  The key thing
is that every variant of these productions will play exactly the same!
Each, different, marked tempo is correct.

I'm sure that occasional errors in marking happened in original
production but it seems rare.  Indeed, this critical aspect of the
roll was carefully quality-controlled, which is demonstrated by rolls
with differing punch sizes marked with the tempo appropriate to that
perforator.  I very much doubt that roll tempo was arbitrarily changed
just for fun or marketing purposes.  These companies were staffed by
serious musicians.

Recutting introduces uncertainty in almost every aspect of the roll,
and of course masks the original production step rate.

Julian Dyer