Good work, as usual. You have a nice tone and range. Your pitch is always right on the money. As you said, you could stand to open up the throat, but that's a hard habit to break. I do the same thing. I pinch a lot on the high notes when I know I need to open that baby up.
Ken says to get used to the feeling of an open tube of air going through the throat, in order to open the airway up. That's hard to do if you're like me and tend to pinch down in order to get enough pressure for the high notes. The thing is that we're not using Open Throat technique when we do that pinch-pressure thing. It works for the note, but it's limited mostly to the "eh" vowel, which isn't of much use lyrically.
I think both you and I will find a new world of tone opens up to us when we learn to open that throat for those highs. It's like overcoming the gag reflex. I'm so used to thinking that closing down is the way to go up, when actually it's the opposite. We have to reprogram ourselves in order to make that the new "natural" feeling.
Besides the Open Throat, the main thing so many of us need to face up to is SUPPORT! There is no substitute for ROCK SOLID SUPPORT. Do you want to power your voice with a Ferrari or a moped? If you are having any issues at all with high notes, there's nothing like doubling or tripling your support. I know it makes a world of difference in my voice. So many vocal issues can be traced back to a need to further reinforce support.
You sound really good, Doc. Please don't think I'm saying anything different. I just know there's even richer tone that can come out of you once you learn to relax into that sound and allow it to come out. You've already got so much talent going for you. Listen to what Ken is telling us about opening up the throat. Go back to your "It's the lah!" basics and bring more of that wide open sound into what you've already worked on for years and years. It will affect every note you sing as you bring that more and more into your everyday singing, as opposed to just doing it in exercises.
Open it up and beef up the support. All of us can benefit from making this our goal.
Keep up the good work!