Originally Posted by QuiltE

Nor would I overlap even it it is not fluffy (eg. Warm and Natural) .... it may not be fluffy, though it is bulky and would create a ridge that might be noticeable in your finished quilt.

Here's a couple of hints I was given for joining batting pieces...
* Lay two pieces on top of each other (yes overlap!!) ... top with a ruler, and then slice down the overlap with your rotary cutter. That way, you have two pieces that are now cut straight and match precisely. Then sew.

* When joining batting pieces, don't make the seams at right angles to the way it will be in a quilt. Angles are actually better, and probably will be less apt to be noticeable in a finished quilt, than they might be if all is kept straight and rigid. Keeping them straight on the horizontal or vertical, you might hit right on a seam, which could make quilting awkward, whether by hand or machine. If on an angle, then you are more likely to just have to work with it crossing a seam.