“Dr Mann lost his case because he refused to show in open court his R2 regression numbers (the ‘working out’) behind the world-famous ‘hockey stick’ graph[.]”
It’s pretty much an admission his work is fraudulent.
Therefore his claims are a fraud.
Therefore most of climate science is a fraud. (Mann is a prominent member of the IPCC, working group 1)
His R2 was likely somewhere less than 0.50, so he massaged to boost it.