Jeff Stein, that is. NE Hurricane for life and owner of Warzone Paintball. He occasionally posts some interesting (and provocative) thoughts over at PBN--which you really ought to read first--as this post is based on his and the follow-up comments.
Or you could make do with a brief synopsis. (Your loss.) Stein separates the pro teams into 4 groups; contenders, pretenders, churn & chum. Alone that produces some interesting debate but his intent is to see if there are ways of looking at the pro teams over the course of a season or more and identify team trajectories perhaps before they might otherwise be noticed. (Who is getting better? Will that trend continue? Who is faltering? Will that trend continue?) And also to set the stage for a dialogue on how that might better be accomplished.
The category confusing things a bit though is churn because the current rules create churn that on the merits might otherwise not occur. A full 40% of Champions teams face the possibility of relegation now with 20% certain to be relegated. The same percentages apply to teams seeking promotion from Challengers. The issue as it stands now however is that Champs and Challengers never face one another. Challengers beat Challengers for a shot at the Champions which means that what really happens event to event is that Champions contains the top 8 teams plus 2 let's wait and see what happens teams. If the goal was to promote the better team on a given day (or at a given event) then the top Challengers from an event would play the bottom Champions and take their spot if they beat them in a head's up match. Then the league could legitimately claim the Champions was always the ten best teams. And the churn category would provide more accurate data.
Keep in mind one reason the Challengers exists today is because a noticeable gulf had developed between the pro division and D1 and one of the hopes pinned on Challengers was that superior competition a step up from D1 would propel the best of the Challengers to a level where some might become competitive with the Champions. We haven't seen that yet but it's early days. It might still happen but given the player pool of pros the next question is are the contending Challengers getting better or are the Champions beginning to tail off?
UPDATE: Got a feeling those 'bounced' responses came from the Challengers division.