One of the reasons I have not gone to pressing both seams to one side is this......it takes too much thinking to get the NEXT seam to be going in the opposite direction! I tried this method with the bearpaw quilt I made cuz I was making that for someone who was actually paying me to do it so I thought it should be done "right"...well, about two squares into it...I gave up on it...I had seams going every which direction and could NEVER match them up!
Do what is comfortable for you to do and whatever works to make your seams match. ....thats about the only advice I can give you.