I'm writing this based on the assumption that McCotter won't be on the August primary ballot. If there are enough signatures, then this is a moot point. As it looks based on speculation, the only name on the ballot for the republicans in the 11th District (MI-11) is Kerry Bentivolio
Assuming McCotter is gone, there's been a lot of push for write-ins. I think it's a bad move for a party to make here. By party, I am referring to NRCC, RNC, MIGOP, 11th District Committee, Oakland County Republican Party, and the Oakland County Republican Clubs. If McCotter campaign wants to go for a write-in fine. If Trott on his own wants to go for it, fine. If Kowall wants to go for it on his own, fine. That's their right as candidates. If individuals want to help them, fine.
If party wants to jump in and use party resources, then I have a problem. I do not see much good from a Republican Party operation jumping into a primary chasing a Hail Mary Pass that is likely unable to succeed. Even if it does succeed, it will create more bad blood between establishment and tea party that is not needed. If you want already sore tea parties to hold their nose and vote for their least favorite candidate running, don't piss them off even further. Stay out, and let the best candidate win.
I'm going to argue this from a nuts and bolts pragmatic perspective.
From a logistics standpoint, we had a somewhat similar situation in the 8th District on the democrat side in 2010. Kande Whatshisnamethequitter was running for the democrats to take on Mike Rogers. Sometime before the primary and after the filing deadline, he quit. Lance Enderle ran as a write in against the quitter. Lance lost to the quitter in the primary. He did get 1703 votes, which isn't bad for a write-in. He eventually got on the ballot because Kande Whatshisname went back to the Philly suburbs. However, the quitter still got 23,228 votes. Granted Lance Enderle had little time for a campaign, but could even Dianne Byrum, Virg Bernero, David Hollister, or Gretchen Whitmer get 23,229 write-in votes? Maybe, but I'd be surprised. Personally, I thought it was impressive that Enderle got almost 10%.
If a quitter can get 23,228 votes in a primary by just having his name on the ballot, what does that say about Kerry Bentivolio's chances in the primary? Bentivolio is a stronger candidate than the quitter, and beat four other candidates in his 2010 race, although not Kowall. Bentivolio's not going to quit. He doesn't have a lot of money, but has some networks with Republican Liberty Caucus (I met him there back in 2010), some tea party groups, and Campaign for Liberty. He's a teacher and a military veteran of Vietnam, Desert Storm, and Iraq. He'll get votes for that, along with the normal vote for whoever is on the ballot unopposed that many candidates get in primaries.
Can Trott get 25,000 write-in votes? I highly doubt it. Can McCotter or Kowall do it? Possible, but I still doubt it. In Michigan, you can't place stickers on the write in space for write ins. You have to spell out the name. McCotter isn't as tough of name to spell out as Rostenkowski, but you have to convince enough primary voters, after this blunder of epic proportions, to go into the booth, and spell out this name when there are other elections on the ballot. Even if one of them get 25,000 votes, it probably still won't be enough. That's just the minimum to have any chance.
In short, there's a very good chance if the parties get involved in this primary for write-ins, that the nominee from the 11th district will be.....Kerry Bentivolio - as it would likely be if the parties stayed out. Frankly, we can do a lot worse than that. I think he'll vote similar to Justin Amash. However, if Bentivolio wins, he'll need a lot of help raising money. That's the biggest reason why the party needs to stay out of the primary. The money spent in the primary needs to be spent in the general. Do you want Bentivolio in there, or Bill Roberts? I guarantee this much. Bentivolio won't back Pelosi as speaker or Conyers as judiciary chair.