Skeg or rudder does effect the feeling when rocking the kayak sideways. Lowered skeg tries to prevent the motion. It might be the same for rolling, however the rudder should actually be in air half of the roll so how could it prevent rolling? Maybe the first part - capsizing is slower and the recovery but half of the roll should go fine with or without rudder.

: My Merganser 17 is a rudderless design, and rolls up easily. I once paddled a
: Prijon Kodiak with a rudder. With the rudder deployed, I found the Kodiak
: to be difficult to roll up. It seems to me that the rudder's resistance to
: righting the boat could be a consideration. Any comments?