I broke this down in another comment, but there's really no evidence that this moderate strategy will work. Democrats win when their base turns out, and they lose when their base isn't motivated. Watching Harris campaign with Liz Cheney doesn't motivate the base. They may pick up some moderate voters in PA (though, again, it didn't work in 2016, so there's no reason to think it will work now), but it's not going to matter if she loses Michigan because of a hard-right position on Israel.