This is interesting since you are, I believe, the only tester who has talked about the TextBlade maybe just being for uber-geeks. Oh, I can see some users simply not giving it any time at all to adjust to. Someone who tries it for an hour and just gives up. But that's about it, from my experience and from what I've seen others say.
You haven't posted much since you got it, but from this post above, you had a problem unit which is certainly going to be a huge negative. And that led to you not using it - which means you weren't getting used to a properly working model.
Not sure what to make of your "using it off and on daily" comment because I never did that myself. I've seen others say that they easily switch back and forth, but that may not apply to you. IOW, maybe the switching, for now at least, is making it difficult to adjust to, thus the feeling that the ordinary keyboard user might not be happy.
Noted your comments about confusion over modifier keys, but also saw that your first post after getting in Treg said you used a lot of shortcuts. This brings up two issues. One is that if the modifier combinations are fairly complicated, the TB can be tricky (though I suspect you could solve some via customization). For example, supposed you needed modifier keys in some awkward combination of command, control, alt, shift keys. Well, there are lots of unused spots in the function layer - thus you could program any of those keys in combination along with whatever character key that is used with it onto one key, activated by a total of three keys (the two key function chord along with whatever key you assigned the shortcut to).
I suppose there are shortcuts that this might not work for, but it's worth looking into.
But my reason for addressing this is that I suspect those more typical users aren't heavy into shortcuts anyway. For those who use some, I'd suggest taking the approach I did. Don't worry about all the things you may want to adjust to. Just start with the basics (alpha characters and the most basic punctuation). Less used, but still important things (think numbers and some other symbols that are less common than basic punctuation you still use a little), you may end up looking for at first. But if they are used very much, those are easy to learn. At least they were for me.
And then I gradually learn to add other capabilities. An example of that was that, at first, I either used my mouse to change cursor position or select stuff. Then I would start trying to use the keyboard sometimes and I had to think about where I was placing my fingers. And then it became pretty much automatic. However, even with that, when I'm moving the cursor, I almost always move up or down a line, or left or right one character at a time. Yes, I know I can do so by word or paragraph, etc. I just never bothered to practice it. Never did on other keyboards either. So even though I know there is a better way, it isn't important enough for me to think about. For those who think it is, well, they just add that after they are used to other things.
But even when there were things I couldn't do automatically or was initially slow about doing, I always was getting enough benefit from the TB to prefer it. Only the shortcut things would worry me, if I needed them. Back then, we didn't have the ability to do as much customization as we can now.
I think the mere mortals just need to start by treating it like a plain keyboard and not even worry about all the other stuff it does until they feel comfortable with the basics.