To be fair, his portrayal of Picard was a bit wooden at times during season 1 and parts of season 2 as well.
But I agree with most of Picard Alpha's points.
In his defense, he wasn't convinced TNG was a real job until halfway through season 1.
True, but surely that shouldn't excuse any wooden-ness. Even if you think your job is only short term, you'd do your best. After having said that, I can't really recall whether I thought he was wooden or not in the first season.
To answer the OP's question I think he learned a lot from all the Shakespearian leader-types he'd played and studied and brought that to the role. It worked well.