The incentive structure of the Republican primary debate cut-off is to promote the crazy even if the goal of the cut-off is to minimize the crazy talk.
The debate will be on August 6th, and it is split into two parts. The main event will have ten candidates who have filed with the FEC and are in a blended average of the top ten positions in live respondant telephone polls within a given time frame. The second part is the kiddy table event which will have every other filed candidate whose campaigns had sufficient funds to pay for gas to get the candidate to the studio.
It is structured this way for two reasons. First, it is purely a logistical move, as fifteen to twenty people on stage would mean no one gets to talk for more than fifteen seconds at a time. Now that is not a great loss as the information to time level is fairly low, but it is a reasonable concern. Secondly, the top-ten feature is a public culling method as the invisible primary becomes slightly more visible. Debates are often one of the easiest ways for a low polling candidate to make up ground quickly and cheaply. This is especially true in any primary process where the ideological universe is narrower than in a general election as a voter is not making significant ideological re-evalatuations when they switch their support between primary opponents. This point is esepcially true in the 2016 Republican Presidential Primary as the issue space ranges from who will cut some taxes to who will cut all taxes, who will bluster first and then bomb compared to who will just bomb, and how much everyone hates seeing working class people get private market health insurance. The ideological space is fairly narrow. So a good debate that rubs a voter’s button the right way will get a very throaty response to a particular candidate.
A candidate who is not in the first debate will have a very hard time getting into any future debate, and thus will have a very hard time raising their polling.
Working with that assumption, five groups of candidates shake out of the crowded Republican field. The first group are candidates who are definately in the debate and project that they will be in all debates until the primaries/caucuses start. These candidates just have to not fuck things up in the debates and start to knock out candidates whose supporters are most inclined to choose them as their second choice. Jeb Bush and Scott Walker are in this bucket.
The second group are candidates who have to hold serve, but can safely assume they’ll be in good enough shape for the next couple of rounds. It splits into two groups, the hucksters/self-promoters (Trump and Carson) and actual candidates (Rubio, Paul, Huckabee). (Yes there is overlap here, especially with Huckabee and Paul). The hucksters will throw bombs as that is what they do, while the actual candidates will try not to fuck up while tearing down a front-runner who is closest to them.
These groups are fairly condifident that they’ll be invited back to another debate. Their incentives are to minimize variance if they are actually running for office as a statement in 2015 can be used against them in 2016. Trump and Carson don’t have this constraint, so they’ll embrace the id.