I do. We stay at the Polynesian and it would seem like such a waste to spend all that money and not enjoy the actual resort.
Last year we planned our meals so that we had Ohana's for breakfast and dinner on the same day. So after breakfast, I went for an early morning swim in the 'quiet pool.' This was great because I was the only one in it. I relaxed, listened to the music and just enjoyed the over all atmosphere. I went back to the room some point later and took a nap. When I woke up, my travel party was back from what ever park they went to and were at the volcano pool. I met up with them and did the volcano slide for the first time. We hung out while my little cousin took part in the pool side games. We had Dole Whips for lunch. After Ohana's dinner, we hung out in the room for a while and at that point, I was ready to get back on the move. I took the boat over to the MK and hung out there the rest of the nice.
Other trips I have spend exploring the walking trail. I did walk all the way from the Poly to the GF and took the boat back. That was fun. I may try that again this year.
I definitely recommend having at least one day (maybe mid week) as a resort day. It breaks up the constant run a round and refreshes you for the rest of the trip.