The McIntyre Creek portage is the most difficult on Robinson Lake side.  It has been several years since I was on that route so it could have changed, but I doubt it.   Way back in 94 we entered PP and made it to Robinson for night 1.  We came thru Sarah and it was a long one day haul. 
There was a fallen tree across the portage entrance making it very difficult to find the McIntyre Creek Portage. 
From my notes on the portage are as follows.  "As we made our way across this portage, we found that it is one of those portages that haven’t been used in a long time.  This is a long and difficult portage.  The over growth made it not only hard to carry the packs and canoe.  But it also made it hard to just stay on the trail.  About 5 minutes into it, we came into a rocky area.  Very large boulders, walking around them was for the most part impossible.  Plus the moss growing around them made them slick and the hidden holes below the moss made for an even tougher passage.  My Partner Todd stepped in one of these holes and fell.  Caught himself with his hand.  But sprained his hand in the fall and we were afraid it was fractured..  I helped him up and we finished the portage.  Which has quite a climb at the end of it.  Doubling on the portage as in two trips it took almost 2 hours."

Robinson is a beautiful lake, I prefer the island site in the northern end.  It would be well worth the effort to paddle Robinson to the north end, even if you decided to paddle back around thru Cecil. 
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