I'm inclined to avoid becoming a principal in the conversation on structures. It seems to be that the difference between blocking and marking has something to do with tempo. There is also the issue of material.
When a rookie linerat gets base-to-base with a Block/Stand Firm bull centaur to prevent an easy blitz on the ball carrier we know right away that it's a marking formation. When the bull does the same to the rat, being far from the ball, it's a blocking formation. But take the ball out of the equation, and we can still be fairly sure what we're looking at; the rat isn't going to throw an early block at the bull and risk a turnover, but the bull is almost certainly going to put the knuckledusters to that rodent. The weaker player is marking, by default. The stronger player is blocking. And the difference is not positional, but material.
Consider the same scenario with two well matched players (say, a Longbeard and a Black Orc), but put one of them on the ground, about to stand. Positionally this is marking, but in practice it will be a blocking tactic for the fellow who is standing, because of tempo.
The poor fellow on the ground can regain the initiative (and tempo) by blitzing, but that action is restricted. So we're led down a path that leads to conversations about marginal initiative, where a coach finds he can gain tempo for his side by keeping several of his opponents players pinned to the pitch.
What's more, because of assists, strength of material is flexible (where mobility, agility, and durability are generally not). The usefulness of an assist has more to do with position than material or tempo, but all of these factors must be accounted for.
These additional factors would distract from the discussion of positional theory. In fact, I cannot see how positional theory can be converted into tactics without considering them.
(Here I am writing about something to explain why I'm not going to commit to writing about it. Avoid typing FAIL. Time for bed.)
I await your further Meditations. Until then-
