I saw the Drai thing, but a few days ago I saw Parayko's name thrown out there for a much more stomach-able return. If they want a Drai, then it isn't happening for us. Parayko isn't that important to me.
Trading a roster player doesn't defeat the purpose of a contending team if it's a "hockey trade" like I think this would be. Sanheim with ice time will contribute right away and Simmonds of course can be an All-star. I don't see why this doesn't fit that (in theory).
Sanheim probably doesn't even crack the Blues current roster this year unless he takes a massive step forward this offseason.
The Blues are already looking like they'll need to either healthy scratch Gunnarsson or deal him given their depth at that position, and he played well last year in a bottom four role. Edmundson, Dunn, and Bouwmeester are all firmly ahead of Sanheim at the moment.
Personally, I don't think there's any chance that Parayko would be considered something on the table in a trade for Simmonds. Not even if Philly was offering major futures plusses along with him. I don't think the Blues have any intention of moving him anyway, but even if they did, that's almost certainly not the sort of deal they would looking for.