I have only been watching ice for 14 years.... young compared to some of you. It has been my observation that the color of the ice in the spring tells a lot about the condition of the ice. A foot of gray punky ice can go very fast with a little rain, some warm temps and wind. The crystals bang against each other and dissipate.
The lake can appear to be socked in, but a very dark gray and then be completely liquid in two days. This happened about 6-7 years ago when the great predictor said it would be two more weeks and it was two more days.
While I agree that we will be later than average this year.... I am watching the color as an indication over thickness. Now.. if I saw two feet of solid black ice... I would be thinking June!