If you are coming into Keats via Russell-Chatterton, it makes sense to take the short portage from Chatterton into/out of McDougall and avoid the "cliff" portage to Keats altogether.  When back on Chatterton, the Split Rock Falls portage is not too bad ... although there is a bit of a climb out of Chatterton until you reach the height of the falls, then its more or less level until you reach Keats.  You might have to do some boulder hopping on the Keats end to move you far enough away from the falls, especially if the outflow down the falls is running high.  

BTW:  the McDougall to Eag portage is no picnic either.  There is s descent sized bog on the McDougall side.

dd