Right, there's really no reason for Trump to participate in the debates anyway - he's way far out in front, so it would only hurt him. Hell, this might even be an excuse to skip them without looking like he's afraid to.
Trump doesn't believe he will win the nomination. If he believed he would win, there would be no problem with him signing the pledge. He believes the eventual nominee will be one of 3 or 4 people he despises and cannot support.
Isn't that a little unconstitutional? I know that hasn't stopped them in the past, but just straight up cancelling a vote of the people is more blatantly fascist than I'd expect from even them.
Yeah in short even the democratic party notes that. When the DNC was sued under the accusation of rigging the primaries against Bernie Sanders. The case was thrown out for lack of standing. In short the DNC said "You are accusing us of rigging the primaries... but rigging the primaries isn't a crime so there's no reason to spend the time proving it one way or the other".