It certainly looks bad in real time, but you're right, if you watch the replay from the board side camera (around the 36 second mark) it is clear his stick rides up the other players stick. Not sure how you do that intentionally.

You could make a case he was trying to intentionally use his stick for something other than puck play (either a low slash or to knock away the other stick) but don't see this as an intentional head slash (ala McSorley).

Do they need to prove intentional slash to the head, or just intentional slash (with the results - e.g. hit him in the head - being inconsequential to intent, but playing a role in the suspension assessment)?

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14 team roto(3C,3RW,3LW,5D,2G,5B,1IR-82 max games)
Cats-G,A,+/-,PPP,PIM,SOG,HITS,FOW,BLKS,W,SV%,GAA,SAVES

C-Toews,B. Richards,Hanzal
RW-Voracek,Stewart,Versteeg
LW-Benn(C),Clowe(RW),Pacioretty
D-Pietrangelo,Doughty,Burns,Ehrhoff,Gonchar
G-Rask,Lindback
B-Emery,Havlat,Coburn,Atkinson,Fiddler

7 team roto(3C,3RW,3LW,4D,1U,2G,4B,3IR-86 max games)
Cats-G,A,P,+/-,PIM,PPP,SHP,GWG,W,SV%,GAA,SO

C-Crosby,E.Staal,Pavelski(RW)
RW-Iginla,Clowe(LW),Wheeler
LW–E.Kane,Pacioretty,Semin(RW)
D–Letang,AP,Subban,Shatty
U-Getz
G-Rask,Ward
B–Kipper,Voracek,Moulson,Burns