No, I'm saying that I disagree with you about how effective it would be, and am willing to put it to the test. If it shows itself to be largely ineffective, we could then move on to your idea, and we'd already be three quarters of the way there. There's no valid reason for any supporter of a guest-worker program to be so adamantly opposed to this route, to the point of holding things up for years. How much has that cost us, in terms of dollars as well as opportunities for crime and corruption?
I do worry that an ineffective guest worker program (which I think your proposal is) would just convince people that guest worker programs don't work at all. And I do think we need one.
The primary goals of a guest worker program are to make sure that we know who and where immigrants are (your proposal would do nothing toward that); to make sure that they go home after their jobs are done (your proposal would only do that for some); and that they didn't bring dependents with them (your proposal wouldn't stop the ones who want to do that).
And, of course, to make sure that seasonal employers (which many of them are) have the work force that they need, without taxpayers having to foot the bill in the off-season. But why would they care whether they're hiring legals or illegals? The answer is, they don't under the current system, or under your proposal.