Here's the deal...lots of people are beginning to notice that at some point in the life of a spider, they exhibit some sign of a "motor control" issue. Keep in mind that normals can exhibit this trait too!
Where the issue comes into play is when you are talking about selling spiders and buyers having all the facts on the issue. There are people out there that, without knowing all the facts, will go on a message board crying and making waves about how so and so sold them a spider that wasn't a spinner but then it did exhibit some spinning behaviors. That's the reason why some sellers don't want to touch the issue.
Some spiders spin to a very high degree, to the point that no responsible breeder would even think about selling or breeding it. Others spin to such a lesser degree that their keeper probably never ever notices it. And just because a hatchling doesn't show signs of spinning, there's no way a seller can guarantee that it never will.
But here's some food for thought - look at how many spiders are making it into collections everywhere...look how many spider combos there are out there...they are obviously eating, growing, and breeding well....so it can only be concluded that spinning obviously isn't any more a health issue in spiders as it is in normals.
As a buyer, just don't be surprised when one day you observe some 'funky' behavior by your spider.
