I use it to baste my quilts for machine quilting. My hands cannot deal with pins. I have no concerns when quilting over the basted WS thread, as any bits & pieces left behind will just wash out.
One suggestion for those who use it in their machines ...
make sure you remove it from your machine asap, so that you don;t forget that it is WS and mistakenly use it as regular thread. I've heard that others have done that and then ended up with a mess on their hands when they washed it or steam ironed it.