I was assuming you were pulling the bobbin thread to the top before starting to quilt. That is standard operating procedure for most quilters. Typically you then hold both threads for the first few stitches so they don't get tangled and create a thread nest. (Some machines are supposed to be non-jamming, so maybe this doesn't apply to them. I'm too old to change my ways, though, I think.)
I do think it's a good idea to fill bobbins at half speed, at least for most machines.