BTW, it occurs to me that —while the partial path '*/groff/*' was a convenient point for me to filter out those files which normally are zero bytes —it is probably too high up in that hierarchy. I.e., there may be *other* stuff inside groff which was not supposed to be zero (and —if such was you case —then those too got skipped).
IOW, this (original):
find /usr -type f -size -1c -not -path '*/groff/*'
should be replaced by this:
find /usr -type f -size -1c -not -path '*/mm/*locale'
for a more accurate results list.
