John Deakin apparently does not think it is that important
http://www.avweb.com/news/pelican/186619-1.html
Prop Cycling
Don't wear the poor thing out, especially on the single-engine aircraft. Many do three or more cycles, often to very low RPM. Not necessary, and probably not desirable, it just prolongs the whole event, making the engine hotter, and going to full low RPM may be hard on the prop and engine mounts as the blades flail the air. Repeated cycles are probably a carry-over from the old radials.
The big old radials do often need several cycles to flush all the really cold oil out of the prop system. This can be clearly seen on cold starts after the engine has been at rest for a time. During the first cycle, the RPM will drop much more slowly than usual, and it will probably even drop erratically, from "slugs" of oil sludge going through. I've had to exercise them as much as a dozen times to get a nice smooth drop. It's also required to cycle them to the low RPM stop at least once to make sure the system has been adjusted properly; the minimum governor setting is generally 1,200 RPM. These prop systems are somewhat different from those on most GA aircraft.
GA props on single-engine GA aircraft do not keep a lot of oil in the prop hub when at rest: There's a big, strong spring that pushes the blades "flat," and it takes engine and governor oil pressure to get any oil in there at all. A single cycle is sufficient to check function, and frankly, this check is unlikely to find any problems. I frequently skip it entirely. If the RPM comes up to nominal takeoff RPM (on the takeoff run), and stays there, that's function check enough.
(You know, I think there are probably people out there who want to put the airplane up on jacks before every flight so they can roll the wheels to make sure they rotate before they taxi. We tend to do a lot of "checking" in aviation that is really doing nothing more than wearing things out prematurely.)
On the other hand, light twins usually have the spring pushing the prop into feather, and the dome will be full of oil at rest, so they may benefit from a few cycles on a cold day. But modern oils don't sludge up as much as the old straight 60-weight in the radials and the GA props should be well-oiled with one or two short RPM drops on the check. If I owned a twin, I'd probably do a feather check once a month in the air, for real. Certainly before and after the annual, and let it go at that.
