My pressed open seams are much more likely to be "off". Nested seams will stay in the right place, especially if you do like Donna suggests and sew in such a way so that the bottom seam points toward you and the top seam points away from you. Then you can take your stylus (wooden, of course) and tuck that top seam under the needle when it needs to be helped.

My tip for dealing with flipped seams is to line up the "rows" of blocks after each row has been sewn together. Then I press all seams on a row the same way. One row goes up and the next row goes down. Lay this all out on a design wall (bed?), Flip row one to the right over row two. The seam to be sewn is on the left side. Do the seams facing you face up (away from you)? That's good. If not, put row one back and flip row two over row three.
When you get the correct direction for the seams, mark or pin which side will be sewn (I have taken this to the machine and sewn the wrong side LOL) and sew down the left side of that row. That seam will be sewn to the right side of the needle. After all pairs have been sewn together on the right side of the needle, sew two to two on the left side as usual. No matter how big the quilt gets, sewing two to two or four to four etc. will always be to the left of the needle and the seams will always be the correct way.

This may be long, but it takes a lot make it understandable. I even learn somethings myself when I try to explain it.

That little lady is adorable! I loved her trick for stopping the seam flip.

Agree, feline fanatic.

Heavy starch and proper pressing helps. I also put a finger on the seam
as it goes under the needle...not right in front of the needle but to the left.
I still get the occasional flipped seam but it doesn't really bother me unless
it's very bulky.

Almost forgot to add that if the seams don't stick I make them stick.
If the fabric had been heavily starched...I dab my finger with a little
water and run it over the seam and press. No flipping.

If I stopped to fix flipped seams, I would never finish a quilt. I do not plan to enter contests with my quilts, they are for family and friends to enjoy. Pets too.

I do admire award winning quilts and appreciate the talent and skill that goes into making them.