OTTAWA — When he cut off his right arm with a “very sharp power tool,†a man who now calls himself One Hand Jason let everyone believe it was an accident.But he had for months tried different means of cutting and crushing the limb that never quite felt like his own, training himself on first aid so he wouldn’t bleed to death, even practicing on animal parts sourced from a butcher.“My goal was to get the job done with no hope of reconstruction or re-attachment, and I wanted some method that I could actually bring myself to do,†he told...