Tactics: Deep Water Fishing

This week's Canadian Tactic comes from the final round game between David Gordon and Armando Valdizon at the RA Fall Open in Ottawa, (Sept.2016). 

White has just played h2-h4, setting up a tactic nicknamed "the fishingpole" -- the Bg5 is the bait, the pawn that takes on g5 is the hook, and the open h-file is line to reel in the "fish"... Or is it?  

 

 

Anyone might go for this line in a blitz game, but David had upset GM Bator Sambuev in round 3, but lost to Kevin Pacey in round 4, so this game was for at least a share of first prize. Imagine there are hundreds of dollars at stake and try to figure out if the fishingpole tactic here is sound:

    • Can Black take on g5? 
    • If not, why not? 
    • If not now, when?

Solution in the notes below: 

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 Round:  Result:

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