I'd hope to make use of this tip, but was disappointed to find output as follows:

diskutil(8) BSD System Manager's Manual diskutil(8)

NNAAMMEE
ddiisskkuuttiill - Modify, verify and repair local disks.

SSYYNNOOPPSSIISS
ddiisskkuuttiill _v_e_r_b [options]

DDEESSCCRRIIPPTTIIOONN
ddiisskkuuttiill uses the Disk Management framework to manipulate local disks.

VVEERRBBSS
Each verb is listed with its description and individual arguments.

lliisstt [_d_e_v_i_c_e]
List the partitions of a disk or all disks. If no device is
listed, than all partitions on all disks will be displayed.

iinnffoo | iinnffoorrmmaattiioonn _d_e_v_i_c_e
Get information on a disk or volume.

uunnmmoouunntt [force] _d_e_v_i_c_e
Unmount a single volume. Force will force unmount the vol-
ume.

Any ideas as to how to clean up the output?

man pages are contain a lot of information for formatting so the command

man man | pbcopy

will result in a lot of garbage on the clipboard. Commands that have plain text results work fine.

Yo get man mages to the clipboard you could use something like:

man TheManpageYouWant | groff -t -e -mandoc -Tascii | col -bx | pbcopy