So, things are going really well lately. My experimentation with my embouchure has landed me on a great setup which is more or less similar to how I've always played, but with a more defined forward focus into the cup. I can now feel the apererture as I'm playing and I know when I'm blowing it apart either with heavy tonguing or not properly setting after breathing (probably from moving too much during the breath). Anyway, my range and endurance have sky rocketed after discovering that I had been trying to switch from downstream to upstream the higher I played. It was bad enough that I couldn't remain at the top of the staff or higher for very long without getting this weird buzz, and losing strength very quickly. Now I'm capable of playing in that range for a relatively long time without problems and it's really exciting. Unfortunately, or fortunately (however you choose to look at it), I'm having too much fun with it, so I tend to want to see how far up I can go too often. I'm trying to not push too hard, but I occassionally try too many times for a high A, for example. I don't hurt myself, but my lips do feel stiff more often because of it. I have a solid high F to F# (I would say F, because I know that I can just pick the horn up and tag that note like it's nobody's business, but an F# isn't as consistent). So here's the question: I know I need to listen to my body and stop when I've gone too far, and I think I'm doing that. However, is this stiffness a sign that I should limit my range extension stuff to maybe once every other day, or maybe even just once every three days? How do you guys work on range extension? Do you feel this stiffness, and how do you deal with it? Most importantly out of all my new developments (which aren't as drastic as I may make them out to sound... I work very hard on the horn, and things are moving along a good pace), is that my endurance is finally getting close to what I hope to achieve this year. I'm just saying this so that you guys don't think I'm just some guy that likes to pick up his horn every once in a while a rip out some high notes. I work hard on excerpts, Charlier, cornet solos, jazz, etc. everyday.