Frank,
This is a really difficult question to answer in a short response. Here is my "take" on it.
First, the formal target shooters are setting up for the greatest chance for an absolutely repeatable shot. Hence the upright stance (foundation the same every time), They are striving for the best alignment in the draw and shot as they can get (depending on their personal form theory).
Second, what (or whose) "trad form" are you using as a comparison? There is much more variation in trad simply because many are self taught, or follow one of the "gurus" in trad archery. Many try to adapt to a known or perceived need in the hunting field. Sometime that is real and sometimes just speculation.
Third, what is YOUR definition of form? What are you looking at as you make a comparison. Just the overall person/package OR are you looking for movement, bone on bone alignment and execution -- the "little stuff?
I contend that IDEALLY form is form. The relation between the "power unit" (arms & shoulders) and the "control unit" (head/eyes) CAN be the same in both types of application but many times the trad shooter is much more "casual" about it.
Minor things like stance and posture, or where the hand is on the face at full draw (side of face OR under the jaw) are things folks key in on rather than the underlying structure of the shot.
There are going to be a million ways to answer this question and there is no "easy" way to answer. To me, form is form, but that depends on what one defines as form. My definition was really given above: hands, arms, shoulders and head relations or positions, overall movement of the same. NOT necessarily body posture & stance.
You mention Terry's form clock. While it MAY not LOOK like a top formal target shooter, it really is VERY good and many target archers would do well to emulate what he shows there. To the untrained eye it may LOOK different, but only because that eye MAY NOT be seeing the important aspects.
Arne