David gave evidence to the Senate enquiry, although as he hadn't archived the email, didn't mention Overpeck. Later, Overpeck put his hand up as the author.
Not long after, Mann et al produced the flawed "hockey stick" graph. As we know, this was exposed by McIntyre and McKittrick. It made a mockery of the old Garbage-In Garbage-Out (GIGO). When Canadian phone numbers were entered, THEY produced the hockey stick - so Garbage-In, HockeyStick-Out (GIHO?)
Ever since then, the charlatan IPCC scientists have been trying to justify the MWP, to eliminate the MWP in order to incorrectly show that the late twentieth warming was unusual (although Phil Jones in a BBC interview admitted it wasn't.
Although we constantly have proof the the MWP happened ( inter alia here, here and here.) it seems the fraudulent IPCC scientists are preparing to "eliminate" it again.