There are two things that make the discussions about concessions sometimes confusing: people who abide by the rules and assumptions of a different edition, and people who base their internal rules or speculations with what the rules actually say / explicitly. This does not help that it's not even always clear whether a derived rulebook works on assumptions cited in multiple editions or not.
To dispel at least some of the confusion, I would like to ask:
Could you clarify how exactly do the concessions differ between the editions (original version / 1.0, 2.0, 3.0, 4.0 / basic version and the usually classified accelerated edition), according to the written rules (not to speculations, rules or habits)? of play)?