I'd have used
"practice defecation" which scans fine
(boris the spider, Tue 8 Apr 2008, 12:08, archived)

in that case
bally good show.

I'd have used some variant of "penetration"
( Mockingbird Practitioner of SCIENCE(TM), Tue 8 Apr 2008, 12:13, archived)

oh
'and attempt ape-on-ape penetration'
(pikey hardly, Tue 8 Apr 2008, 12:18, archived)