I guess I am the odd one out here. I press my seams open and stitch in the ditch all the time. I have never had a seam strength problem. I have been doing it this way for over 20 years.

when ever I did stitch in the ditch method, I pulled slightly on the seam as I went along and stitched very close to it. when I let go, the fabric closed over my stitches nicely. but still, it wasnt' directly on the threads. Eleanor Burns of Quilt In A Day does this often.

I do it...i just stitch about 1/8 inch away from the seam....no problem.

I also press my seams open,of course this takes longer than pressing to one side! But the joining up of the the blocks is so exact,
If I am going to SITD I piece with a smaller stitch

As an open presser, this is what I would recommend as well. I usually quilt about 1/4 inch from the seam. I hand quilt and want it to show instead of being hidden. But that also allows for the fabrics and/or pattern to be the focal point and not the quilting.

but that's not "in the ditch".

Press them open to reduce bulk and then use the serpentine stitch centered over the seam. Makes a nice wavy quilting line that is perfect!

I don't press my seams open and I don't do STD. If I do straight line quilting, I sew about 1/4" away from the seam. Looks much nicer to me.

I usually press my seams to one side but there are some patterns that really work better when you press your seams open. I haven't had any problem with weak seams or batting coming through the seams when I have pressed my seams open. I have also stitched in the ditch with open seams with no problems. I have never done this on a large quilt but rather on hot pads, place mats, mug rugs...smaller things. On quilts I like my quilting to show so rarely do any stitch in the ditch on them.

I don't understand why people are opening the seams? In some situations it may be necessary but it's weaker and looks bad because the thread shows. You should see them on the long arm...what a mess! Some use white thread throughout the quilt. Yes...then you have fun coloring all your thread so it doesn't show which may also further weaken the thread.<object type="cosymantecnisbfw" cotype="cs" id="SILOBFWOBJECTID" style="width: 0px; height: 0px; display: block;"></object>