interesting -
i was just thinking it was interesting on how much some us rely on our 1/4 inch presser foot - and how many instructions say to "sew a SCANT 1/4 inch seam"
For my purposes, my older Pfaff has a stitch selector - it's #1 - where I can move the needle to 13 different positions. It's probably only a couple of threads difference on each position, but it makes a difference, and I set it on 2 going to the right.
On the Singer 237, the presser foot that came with works perfectly.
I did buy the 1/4 inch presser foot for the Pfaff, but I seem to get better results with changing the needle position.
I think with practice, most of us learn what works for us -
I do the graph paper check now and then just to see if I'm still "on"