If a fuel line is old enough it will deteriorate regardless of what you run through it. If the saw runs a little ragged while cutting you might want to open your screws a little/richen the mixture to account for the load. I forgot to do that a lot.
I sold Stihl but the Craftsman was a good saw. A Poulon?
Having said all this, I don't know if E10 would hurt a fuel line. All I know is most plastic fuel lines should be replaced ever couple of years anyway. Just feel them and see if they are getting stiff and discolored. The gunk in the carbs and screens comes from old gas no matter what blend it is. I'm 57 and it's been this way all my life.
Most people put their mowers and weedeaters up for the winter and have to have them serviced or replace them next year because the old gas made gunk in the carb. It has nothing to do with ethanol. Some of the other "stuff" is dirt, grass clippings, or sawdust. Particles in gas doesn't have to be some government conspiracy to foul your lawn equipment. Always run the gas out of your carb when you won't be using it for a few months. If you lean out a 2 cycle and run at full throttle, you WILL burn a piston. Plastic fuel lines do get stiff and crack, period. It's built in obsolescence.
I think this particular craftsman saw is made by Poulan.
Yep! And this Craftsman Saw is old enough for that to be the underlying reason for its disintegration.
I have, OTOH, burned up a lot of string trimmers over the years, and I am now suspecting the ethanol as the reason for that.