Are you referring to the three finger drag and drop? In 10.11 it has been hidden and moved from the trackpad settings to accessibility. Not sure why they did that...
Was playing with this capability on a rMBP and my woman's new MacBook. The way in which Force touch interfered with drag & drop annoyed the Hell out of me. So, I disabled Force Touch and the problem was solved.
Been dragging and dropping pretty much the same way since 1992 or so. Not gunna' change that now, so I can get a goofy snap preview of a couple apps.
I had some issues with this at first. It can be a bit finicky between a click hard enough to grab the item and a click hard enough to do a preview. I have enable dragging off on mine. For reference, pretty much everything is checked off in my trackpad menu. I'm using the magic trackpad if that makes a difference.
I just deleted by Magic Trackpad 2 (in Preferences > Bluetooth), then plugged it in again via the lightning cable to re-pair. And amazingly drag+drop now works just the way it should.