I have started using 60 wt Aurifil or if I'm using 50 wt. I press my seams open. That way I can use a regular 1/4". "Scant" means something different each time depending on thread and fabric thickness. Adjusting the needle can take a while to get the right combination. I've sewn garments for years and had no fear about an open seam not being strong. If an open seam can hold clothes together through wearings and washings, I think it will hold a quilt together. Also they are easier to hand quilt and many award winning quilters use open seams.