By playing with this today I realized that we can save a lot of processing and time by setting the connectWith option AFTER the .sortable() is initialized!!
}).sortable( "option", "connectWith", '#story>.iteration_frame>.iteration_container.allowdrop' ); For whatever reason setting this option AFTER initialization saves us 4X the time!!
The bottom line?
Plan, large page, all initiatives all items everybody,
Time to do JS bindings (browser is blocked for that time so it's a time user feels!)
Before: 16 935ms, 253437 calls
After: 5 617ms, 179336 calls
Work page, same selection
Before: 1200ms, 136 668 calls
After: 510ms, 39565 calls
The more sortable elements on the page the bigger the benefit!
You can look at that page on the forums: