I don't want to turn this into another Case vs TJ thread. But I don't want to talk about the Dolphins, and your strongest opinion in the blog is about Keenum.
I don't see a reason in here why Keenum has to be spectacularly better than Yates. I do think Keenum has to be better. I think Kubiak (and any other NFL head coach) wants to put the player in that gives his team the best chance to win. I don't think he would play Yates over Keenum if he felt that Keenum was the better QB. Regardless of height and experience.
I don't see that as a factor in who would be the backup. If the Texans like both QBs a lot, I think they keep them both. On the flip side, if they aren't comfortable going into this season with either as the backup, maybe they should be taking a look at the waiver wire. I think the equation is pretty simple. The best QB between Yates and Keenum should backup Schaub. If the 3rd best QB is one of the best 53 players, then he should be on the roster. Finally, if the idea of playing either at QB keeps the Texans up at night, keep looking.
My thinking>
If there is a tie between two players, the preference will be for the player that has real game experience and NFL measurables and can't be stashed on the practice squad. So unless Case is no brainer awesome and TJ is no brainer miserable, any equivalent sort of performance favors TJ because of roster flexibility issues and project to the NFL measurables.
Game 2 is the key game because CK is getting the true backup sort of snaps. Game 3 will have fewer opportunities. And game 4 is a scrub fest with the bare minimum of starter guys playing just to get through the game. So he needs to very much take advantage of the rare opportunity he has received. If he excels, maybe he gets the backup snaps game 3.
It is rare. Can you ever remember Kubiak flipping who the backup is from game one to game two?
Kubiak has repeatedly has said not to read too much into CK going 2nd. He is trying to create competition that is fair. He repeatedly says he wants to make snaps even. To see what he has in CK against better competition, and to light a fire under TJ who should be playing better than he is going into year 3.
The creating real competition thing is real. Sometimes in practice when CK faces the better defensive group it looks like clown school stuff from CK. Mentally, you can see CK's improvement because he looks much better this year in 7 on 7s than he did last year. 11 on 11s are a bit more of an adventure.
(FWIW, the offense did not look good this week in camp w/Schaub missing part, then coming back. In particular, CK looked horrific the day that the U of H football team came out. Like throws off back foot into zipcodes where his receivers were not at. That was a very Kubiak facepalm day).
As for 2/3 QBs on roster, the Texans have gone both ways. Last year they carried 3 because Schaub was coming off injury, and then they booted Beck (who actually looked the best in preseason of the backups), after they needed bodies in different parts of the roster.
The bottom of the roster may be important at the outside linebacker/wide receiver/oline positions. So if you can stash a QB who knows your system on p squad, it is better than having to have him hold a clipboard on the 53 man roster. A lot of this has to do with injuries on other parts of the team.
I do think the backup QB position keeps the Texans up at night. I think the 2011 season they had to coach their asses off trying to deal. I do not think either Yates/Keenum are the future of the franchise guy or are even the 1A QB option that Sage Rosenfels was. But even backup quarterbacks are expensive, so trying to find a developmental guy to work with is a hard and an imprecise science. The Orlovsky experiment best illustrates. You can look at tape and talk to people but you don't know how he is going to be mentally and physically under your system until you work with them.
I agree that if Kubiak thought that Keenum was better than Yates, he would put Keenum as backup. I don't think he thinks that--but he wants fair tools to evaluate so this week he is seeing what CK can do against better competition. And it isn't just the results of the play--it is the decision making, clock management, handling situations as well.