Maybe I’m giving republican campaign functionaries too much credit(not implausible given Trump’s nigh-magical ability to attract the best people and, when he does manage to pull one that was once good at something, reduce them to a husk); but it wouldn’t be entirely surprising if the problem is specifically what isn’t scripted.
With Trump it’s always personal(and, while some attempts fall flat, you can really tell that he has a bully’s eye for a target: not sure ‘little Marco’ or ‘low energy Jeb’ ever recovered; though ‘rocketman’ never really landed); and he’s clearly got something personal against Obama, less clear if he’d actually object to Biden if they’d met under different circumstances; but he’s been the designated enemy and humiliator of the last election, so he certainly objects to him now; but I’m not sure he really has any strong impression of Harris to work with.
