I'm curious: Does it matter if peppercorns are whole or crushed. If so, why?
Are the oils or phenols on or near the surface of the peppercorn and, therefore, extractable in the beer?
Does crushing increase utilization (i.e., by breaking the outer layer, or increased surface area, or access to the internal part of the corn)?
Does adding it to the last 5 minutes of the boil do anything more than sanitize the peppercorns?
If so, then recipes should take into account pepper "utilization" by mentioning when they're added, how long they stay in the wort or beer, and whether they're whole or crushed (e.g. coarse, medium, or fine).
How about other grains or spices (e.g., Grains of Paradise, Star Anise, Juniper Berries, Ginger)?