Apparently these guys don't know what 'dilatant' means. Since they must have purchased this stuff under the name '3M dilatant compound' (since that's what the manufacturer calls it), they must have wondered... They should have googled it. A little "I'm feeling lucky" action, and 5 seconds later they would have known that the more force they applied to their seperation attempts, the more resistance the putty would provide. In the end, they didn't need anything sharp, or particularly strong to do the job, they just needed to cut very slowly.

Or they could have e-mailed Crazy Aaron and asked him how he does it.