I think I can see where your going with this and honestly, think it's got some potential. Your getting your practice in on 'real' quilts, without having to 'worry' about the learning curve errors on the LA, or wasting 'practice' materials. In short, your basting the quilt on the longarm, just to be able to take it home and quilt it, and if you end up liking the initial quilting w/the WS thread, you can always quilt over the WS thread with regular thread. The zipper suggestion would save time on loading the quilts, that would be a plus, if the LA frame has that option. I think I would first try taking a class, to see if LAing is appealing, or not. The downside might be the time spent between LA visits. The longer between visits (maybe because of my senility), the harder it might be to learn the LA process? With either route though, it would seem something is being wasted, the material used for practicing, or the time spent duplicating the efforts?