I like Perron. Seems like a great dude, works hard, was the middle-six glue the Blues needed a couple seasons ago. Looked very good for Vegas.
Okay, he sucks in the playoffs. I don't think it's lack of effort or unwillingness to pay the price, though. I think everybody else just ratchets it up and Perron's intensity was already as high as he knows how to get it.
BUT, I also think that was the same for Oshie until he figured it out with Washington. And in Oshie's case, I really don't think it was linemates or role. He was up and down against Philly, then suddenly had a hattrick against Pittsburgh, his confidence soared, and he's been good for the Caps in the playoffs ever since.
Lots of players have been playoff failures until later in their careers. At that price, with the Blues' current needs, that's a fine gamble to make. Not exciting, but fans were really "meh" about Perron's signing on for a second stint a few years ago and most were pleasantly surprised.