Rippetoe: "heels about shoulder width apart, toes pointed out about 30 degrees....", "if the toes point forward, as is usual with a narrow stance, the knees will go forward too [making] a good depth hard to reach." "Stance will vary" with a variety of factors. Basically you want to make sure that you have "the corret neutral relationship between the femur and the tibia, so that no twisting occurs...." "Bodybuilders frequenlty use a narrow stance squat to develop contest quality quads." "It is very common to see lifters at all levels of proficiency squatting with their toes pointing almost forward. The really strong ones do it to increase the joint tightness....and the novices haven't been corrected yet."
Basically not a good thing unless your body is built very oddly. Your feet should be angled so that when you force your knees out as you squat, the knees track right over your feet.
As for why you were able to increase by 25lbs, first 25lbs is a perfectly normal increase for novices like you and I. The mechanical advantage given by a technique or even improvement from workout to workout is amazing. I was front squatting barely 45lbs a month ago and am now at 135lbs. Simply because as my technique improves the weight goes zooming up. When you think about it, if you can bench press 150lbs or something, why wouldn't you be able to front squat much more than that? Technique is the only reason.
Maybe your kickass coach, though, is trying to strengthen your quads. I would say a good coach, who actually sees you in motion, is far superior to any advice you're going to get here.