Great post! Really appreciate the depth of the analysis and the methodology you used to evaluate the value of the deadline deals.
Re: Jets TDL, while I agree with all of your analysis I think a final grade of D is harsh. In essence the Jets TDL was Hayes and a bunch of minor moves, none of which will move the needle much either way. The Hayes deal itself I'd rate about a C/C+. He's an extremely solid player, but it's not as though the Jets got any kind of bargain. They basically paid the 'going rate' for an impactful TDL rental.
You're rightly critical of the Petan deal, but let's face it, he wasn't going to be any kind of factor in the playoffs barring mass forward injuries. It bumps the Jets grade down a little, though.
Overall I'd give the Jets TDL a C. Chevy did what needed to be done, but it wasn't a heist or even an overly impressive haul.