Feature request: hidden sync timestamp

I'm busy upgrading the steamgifts sync tracker userscript to work on SGv2, and the way the new site is built means I can make the script far more useful and user-friendly than before.

(some technical background information - you can skip this paragraph) In the past the sync tracker would look at your list of games and groups whenever you visited your sync page, which worked well, but required the user to periodically visit that page for the script to update. On the new site the game and group lists are divided into many pages, so I'd need to load each of those pages in the background, but I'll want to be very careful not to do it in such a way that it causes unnecessary load on the server. Since the tracking now happens in the background I might as well make a add a button to sidebar which the user can press to trigger a scan of his games and groups from nearly any page in the site. The only things I don't like about this are: (a) this still requires user intervention and (b) users can press the button multiple times between syncs, causing background page loads that don't need to happen (I don't want to risk slowing down the server)

I'd like to request a feature which would help me immensely, as well as anyone wanting to make a similar userscript. If there was some way a script could know the timestamp of the last sync from any page in the SteamGifts site then it would remove any need for the user to manually trigger a scan of his games and groups (and I could avoid adding a button to trigger scans, preventing the user from pressing it unnecessarily). It needn't be visible - just a data-sync-timstamp="1422721378" attribute or whatever added to some element on the DOM tree, or a global variable in Javascript.

Would this be possible?