I was/am a teacher.
Yes, learning a consistent 1/4" seam is impotant but it is the way a teacher goes about it that makes all the difference in the worl. It is one thing to stand over someone and say "Rip it out. It's not right." as oppsoed to saying "That was a good try. Let's see what we can do to get your seams closer to 1/4"." Especially since we are adults and should be respected as such.
As for LQS classes: I am convinced that the vast majority of the "techers" should not be there. One class the teacher showed the technique one time and then sat there while we struggled. One class the teacher did not like my approach and fabrics and thus I was ignored the whole class. One just was there to sell kits. I am saving my money for fabric. Learn more from videos on line.