I agree w/chikkie, lostarts and suzybcool: at least 2 windings from the swift. Most hanks I get of the specialty-type (hand-dyed or expensive—$15 - 20 per hank) need at least that many windings to get a nice, soft cake.
As they come off my swift, many brands (Madelainetosh DK & Malabrigo Sport are famous for this..or is it just me?? I recently had to cut one Malabrigo Arroyo hank completely up to remove it from the swift because it was so tangled into itself, even though the company ties their threads in 3 separations in each spot.... )
But they do knot up several times inside the hank while winding off and this causes the winder to jerk and wind on very tightly. I, too, do need to set the first cake on the floor and re-wind it at least once more, hand-pulling it out of the first tightly-wound cake to loosen it. I have very soft cakes this way and don't worry about doing them all up for an entire project at once.
3 windings I'd worry about; each winding will tend to give the yarn a bit more of a twist. 3 might cause too much twist to the yarn and the subsequent garment *may* take on a bit of a bias after knitting up. I don't want to take that chance. On top of that I've got a bit of a frozen shoulder and continuously pulling a yard or 2 out of the first, hard-wound cake to loosen it up before rewinding the yarn really aggravates it. I cannot do this for a very long period of time all day long. Twice is enough for me.
Bobbie R