Is there any proof of an elastic effect then training a big man on the lagging small man skills (or vice versa)?
Sorry, I didn't understand fully what you mean...can you explain a bit better? You mean, if there is negative elastic effect on big men if they have bad guard skills? As far as I know, there shouldn't be. But I have never trained big men, so maybe someone else should have a better answer.
at least starting with this season there should be one, and why shouldn't they exist before it mustn't been a big one.