I just tried this and it should be warned that this resets existing "three finger drag" (for mission control and switching desktops) to "four finger drag". This took me a while to figure out after thinking something was seriously broken, even after going back and disabling the new setting you mentioned.
To be explicit, the fix is to go into the trackpad options, more gestures, and change "swipe between full screen apps" (poor name choice) to three fingers.
