Sounds to me like a solution looking for a problem.
I'm not currently playing in multiple leagues but when I was, it wasn't a problem to go to the appropriate thread on each site. Doing it all from a third party website saves almost no time. You open the OCC site, find your match thread and check for updates, and then it takes a few seconds more to go to the AnotherBBL site so you can look at your match thread for that league.
If you have enough spare time to be playing in so many leagues that the above starts to take a significant amount of time, then you also have enough spare time to be looking at a few different league websites.
As the person who deals with the techy stuff for another big league (I built the site, and developed replay parsing tools), I'd be questioning precisely what benefit there is to justify the amount of work involved to integrate such a system into the site for that league. I don't mind doing the work if it is worthwhile but I don't see this as worthwhile.