I think there is a lot of ways to look at this. Given his cap hit, I'd rather get rid of him and rid the contract.
But they might be looking at the situation that he has a cap hit whether he is on the team or not, so if you can do with a couple million hit higher than an outright cut, then he might be worthy to be on the team as a backup. I can understand this. Because it probably nets out to the same as signing someone else to be the backup.
Waiting until after FA starts and talking right before the roster bonus gives us a great amount of leverage in a couple of different ways.
1. He doesn't have much time to negotiate or think it over, it would be much more of a take it or leave it offer with a small opening for slight revision upwards.
2. It helps the Cardinals save face when offering such a steep cut and to Kolb in accepting it. If we were to ask him to take such a major cut while having the cap room we have, it looks worse then if we can come to him after signing a couple of guys eating that cap room and telling him 'look we don't have the cap space we need and so we really need the cap room'. (and if we add someone like Reggie Bush it gives us an additional selling point of having another weapon for him...perhaps they'll even lay out to him some rudimentary plans to address the OL)
After signing a couple of free agents (potentially of course) then the take it or leave it restructure gives the Cards more leverage because they really have to do it, and makes them look less like buttholes for asking for such a big cut. The fact would then be that they are up against the cap and need to create room for some more moves and that because of this they can only offer such a low rate restructure. Good front offices have a way of using being low on cap space as a means to create greater discounts and from more people overall.
They also will most likely use the bonus as a means to say hey look you'll get the bonus in addition to the minimum contract (or thereabouts), and thus this season you'd still be paid a total of 3 million or so. Maybe even 4 million. But if you decline you'll be cut, lose that bonus and salary and take your chances on the open market where he will probably get less. He will not get Matt Moore type numbers. His best option imo for the greatest total money coming to him will be from us.
If he stays I still go after Palmer with the same fervor I would if Kolb wasn't under contract. But I can understand keeping him as a backup.
Hell in a sense it could be used by the Cardinals as a way not to look so needy during any potential Palmer negotiations. Of course, we actually ARE that needy regardless.