Sean,
You are talking about a golf course that suits you but not some others. Assuming most people are happy playing in around 6,000 to 6,400 yards, it makes sense to try and get those tees as close as possible to the previous green where practical. If you don’t accept a walk back or two, that is the total length of your course. Which is Ok but it is going to turn off a %ge of low handicap golfers. So as long as the owner accepts that.
You referenced the 4th at St Pats which most certainly classifies as a walk back for the 6,900 set of tees. But crucially, Tom has the most used two sets relatively near the 3rd green. Putting tees right next to greens is very difficult in that landscape. Even more so in a place like Carne.
With walk forwards (which I know you are also talking about), the same applies. But I also know you are referencing modern monsters here with 5 sets of tees and huge gapping. Where it becomes frustrating is where the walks have been built in to a modern course on tame land that effectively has been scaled up / stretched out to try and be all things to all people but is really just focusing on the elite golfers.
I think it is time we do another Armchair Architecture competition. I have a real site in mind. I look forward to your participation.
EDIT: Reading your post again, I see you are talking about back tees on some but not all holes. I am on board with that kind of idea. In fact, it is pretty consistent with my general approach.