To see or not to see.
The other day, PD came up the river bank to where I was standing and bummed a fly off me. Nothing unusual about that. But then, after I handed him a #18 nymph, I had to watch as he squinted, and cocked his head to one side, and held his hands out far in front of him. (this was before he got specs, but I think it was a #8 woolly bugger he was struggling with) I obliged and lent him a spike to clear the hook eye, but the show continued.