Knitted items made from wool actually can withstand and benefit from a fast (but short) spin cycle. Things like blankets, sweaters, etc.... not only will dry faster but won't be so heavy (especially the former) water laden when hung on lines to dry.
Polyester and other man-made fibers for most part are hydrophobic, they resist water and don't absorb that much if any. Short spin is all that is required, but you don't want it too fast due to risk of creating creases.
If you've ever washed poly/cotton blend sheets with "normal" cycle and noticed after even ironing creases still remain no matter what one does, that is what happens to the polyester part. This will happen especially if tub was too crowded for synthetics but just fine for normal fabrics.
Ideally "easy cares" fabrics or items should mean just that, things come out of washer and maybe dried or ironed (depending upon fiber content and manufactures instructions) with little fuss. Otherwise what is the point?