Pete CZ (and others)--The hike invovled in reching Polk Patch from 441 is a bear (the final two miles going back out, at any rate), but there is an alternative well worth considering. That is to make a four- or five-day trip starting at the upper trailhead and finishing at the lower one, changing campsites two or three times as you go. It involves some planning but also lets you see the many faces of Deep Creek and other than a modest climb up the ridge where the trail leaves the stream at Bumgardner Bend, is pretty easy going.
Someone also mentioned trail access to Right Fork above Polk Patch. While the trail isn't visible from the creek in many spots, it is seldom very far away. When you decide to stop fishing, just strike out to your right (as you face upstream) and most places it isn't much distance at all to the trail. Now Rocky Fork and Sahlee (feeders of Right Fork)are different propositions.
Yet another point was made about Right Fork being tight fishing. I guess it is a matter of perspective, because I've never thought it particularly bad. However, if that troubles you and you don't mind some bushwhacking, climb up to the Fork Ridge Trail from Polk Patch campsite and then drop down to Left Fork. It is wide open (just no trail).
Finally, I guess I never thought much about the quality of the fishing at different seasons when it comes to Right Fork. I think, on reflection, I would agree April and May are prime, but then that's true anywhere in the Park. I've always been able to catch fish in good numbers in and around Polk Patch no matter what the season, and late October/November see the big browns moving up into this area
Maybe this weill help a bit It's an area where I've spent a world of time.