Yes Shetlands can be roo'd, which is what hand pulling is called. It is also sometimes also called plucking but that is totally misleading. Somewhere on here PDOlamb has posted a link to roo'ing. I haven't looked at it yet, but someone has commented that it looks stressful for the sheep, which it doesn't need to. It does however take a long time, but can be done in several sessions if both sheep and human get fed up. There are various different ways of doing it - peeling the whole fleece off in a oner, for which you need very strong hands and some idea of what you are doing, using a knife to brace the wool against as you pull, or pulling the fleece off one handful, or less, at a time. This last is my preferred method, as it leaves the sheep looking very beautiful and the wool can be spun directly from the bits roo'd off. I tie my sheep to a gate by a halter and sit against it, with one knee stopping it going forwards and the other stopping it going back. I then check that there is sufficient 'rise' in the fleece to be able to roo ie the thin line showing the slower winter growth is a good half to one inch above the skin. Starting at the shoulder, I take small handfuls of fleece, gripping firmly, brace the skin with my other hand, and wiggle the handful until the old and new wool separates at the rise. This proceeds handful by handful across the sheep. Usually the britches are not ready when everything else is, so you are left with a funny looking sheep, but it will be ready to finish in another couple of weeks.
First shear sheep can be more difficult to roo, and occasionally you will get an individual who just hates being roo'd, but most don't object. It is a great way to prepare a Shetland for showing.