The fact that the Constitutional Carry bill has some big oversights like forgetting a second tier of optional shall-issue permits for reciprocity with other states makes me think this is a throw-away bill.
Even with Republicans having control of both chambers and the governor's office, and having stood up to the public unions, they're not going to take a beating for passing permit-less carry.
I suspect that the constitutional carry bill was introduced to mollify those who demand nothing less than permit-less carry ("See? We tried."), and also to make it seem like they were being reasonable by passing a bill that requires permits, rather than that risky and dangerous constitutional carry bill.
Of course, the only reason that Republicans are going to pass a carry bill is because they imagine that they need to pass a carry bill. One of the reasons that they never needed to pass a carry bill was that Wisconsin never had one. (For those of you in Rio Linda, please reference the quote from the letter in my first post).