Hi Bryan,
If you put a hyperlink on the button, then that triggers a synchronous GET on the server.
If you put "send new value to server" then that triggers an asynchronous GET.
Putting these 2 together on the same button will lead to weird stuff happening.
You don't really have control over the _order_ of the Gets, so having the button do _both_ these things is not ideal. Certainly not if the one will have an effect on the other. It's also possible that the browser will only do the synchronous get, as the "current page" goes out of scope when this GET is done. It's _possible_ that I could fiddle with the JS a bit to try and make it more predictable - but that only covers the client. You still have no guarantee of the order in which things will happen on the server.
Rather, get all the information you want into the URL and process just the Syncronous Get.
Cheers
Bruce