Anh, it's off and on at this point, but more on than off (good than bad). I'm being forced to play pretty hard in the group I'm playing with now, and it seems to be doing me some good. It's hard to explain, or maybe I just don't have the patience to type it, but in the past I never had to really depend on my corners so much as I had to depend on the tissue in my lips to withstand what I was playing. I cheated back then... I used to pull the mouthpiece down so that less top lip was in the cup, and I could just blow a lot of fast air by my lips and play really high. Well, since I've gotten serious again I've wanted to learn to do it right. And now I'm learning that my corners really have to be strong to support me throughout the day. Sure, on a good day, that thin thread of an aperture is there, but when I'm tired it disappears and my tone goes to hell. I think this is most of my problem. I'm getting in better shape now, and I have consistent high D, D# range. When I'm fresh I can easily play double G, Ab, A, but then the next day I'm toast. It's all about the mechanics!!!