I am not seeing the similarity. Fwiw, when I first got my gym set up, I was doing 2-3 movements per workout. It changes often, usually, 5. Usually 3 large lifts, 1 core and 1 accessory. I’ve never done more than 6 -7 on one day. The fact you are leading off w2ith this analogy, and you are one of the best here, makes me wonder why there is so much misrepresentation of my program.
The similarity, as I seen it, was the need to cover every single muscle in the body with a specific exercise of it's own. The comparison from yours to Matt Z's program was simply to show the opposite end of the spectrum. With about 10% of the exercise selection as you, he still covers the same muscles and movements, at least to an extent. As for which one is "better" - probably whatever one you're not doing, either that or, whatever one you believe in/will enjoy/will stick to. Kind of irrelevant anyway so, moving on....
I stated it in my OP.
“Any pitfalls for this sort of routine in general?”
While I understand my specific goals would help all our experts to build a better program for me, I was thinking some general thoughts of this program might emerge.
Well, in general, I feel the program is generally ok?
Anyway, excuse the sarcasm. Most of my training "philosophy" is about improving "performance". That's general, but I break it down for each client. For example, one specific goal for a new untrained and out of shape female fat loss client may be to do push ups from the floor. Sometimes, they don't even know this is a goal, they just want to lose fat, aren't interested in "performance" (at first), so they just do their program as written and coached. However, I know that improving performance forces change (in physique), and improves health, so "my" specific goals for this woman will essentially take me to "her" general goals, "lose fat".
In your case, and staying with the example above, I don't see a direction to move in. There's nothing to work "back" from. I also have a bit of OCD - I need something to aim for! So, I struggle to give "general" advice. I need some kind of progression towards something. Right now as far as I can see, we're shooting a machine gun full of exercises into the dark. If that is the "general" goal, then I think the program is perfect. In fact, I don't think you can go wrong. You WILL improve in the majority of exercises you are training. Also, your heart seems set on it and I believe this is one of the most important factors - "believing" in what you're doing. Since your heart is set on it, then I would say just go for it.
Like “I find doing Lower first makes more sense” Or “Why do you think this is better than 3 Full Days/ week, oscar”
Generally, I put the training day with the biggest priority first in the week. For example, past 6 months I have prioritised Military Press, so Upper is first. If it was Squat, then Lower would be first - that's what makes sense to me.
As for the structure - you're training your full body 3 times per week, over 4 days. Nothing wrong with that at all.
or explain why doing both Front and Back Squatting was wasting time, causes a stalemate of sorts.
I’m not sure everyone is saying “Why???” to the Upper/Lower/Full/Full as much as they are the list of exercises. I’d like more discussion on the former; and more “proof” that doing two similar movements is less productive, for a general goal like mine.
I think the upper/lower/full/full is fine for what you're training for, and can be for lots of other things.
I sometimes like two similar movements. Actually I do quite frequently. I'm also not against 2 squat variations over one week (i've went with more myself, Box Squat, Front Squat, and OH squat, for example). I think some movement/muscles need more volume i.e. rowing/pulling. I think you need as much as possible. I could to 10 sets of 10 DB rows, or I could do DB rows, then add inverted rows (to get the added "core" benefit), and face pulls (to get the added external rotation and emphasise on rear delts). Infact, last night, I done, in a circuit format - Pull ups, chest supported rows, prone YTWI's, and face pulls. I could of just done DB rows but, I feel the slight variety is more beneficial. I have no "proof", it's just a feeling.