Not yet. I don't anticipate doing more than two. For trailer stability (and I'm not a physics/mechanical genius, so could be dead wrong) one bike would have to be on the central point; two bikes on the outsides. I anticipate the bike(s) tracking like a second trailer, similar to a tractor trailer fifth wheel. This has been a new project for me and this feature is just waiting for an experiment phase to happen by: the need to work on two bikes at the co op; finding a discarded bike/someone gifting me another portable mess that I intend to cannabalize. I have a modest, and beloved, trio of bikes that I ride. If there is to be a catastrophic failure I don't want it to happen with them. So I'll check back in once I've tried the QR blocks. As a grocery getter it is proven. Last week I carried approximately 20 lbs of frozed green beans in a second cooler, packed with just four plastic bbq bottles of ice, and assorted other edibles. Green beans all stayed frozen for 10 miles/1+ hours.

Now to find an abandoned bicycle

As an after thought: towing a second set of linked objects I consider suicide at moderate to high speeds (for a bike). My plan, in these situations, is to slow tail it to my destination. Having to brake at moderate to high speeds would just be inviting the load to jack knife. I'll err on the side of caution and safety (if possible).