I cut with the main body of the fabric to the left and my strip to the right--my strip is not under the ruler. But several months ago I noticed on many videos that after squaring up the fabric most instructors flipped their fabric and cut with the measured strip under their ruler. I posted a similar question on this board and got the same responses as you did--both methods are used and whatever works for you is OK. Just use your method consistently for the cutting of all the pieces of a quilt--don't change in the middle of a project!