Deep Wounds applied with Mortal Strike, with skeers stacked 17times = 92% crit chance on application
http://imgur.com/hllH9G8
Deep Wounds applied with Thunderclap to three targets, with skeers stacked 17 times = 92% crit chance on application
http://i.imgur.com/UL0w3ba.jpg
Just did 5tests per ability, so luck may just have been on my side, but all of the tests gave the same results.