In the airline i fly for the EVAC drills are completed from memory - each pilot has their own specific drills to accomplish. Then, commanders discretion, if not life threathening the F/O reads the QRH to ensure all is covered.
Id like to point out that in the Boeing QRH in checklist instructions it states that "
The pilot flying may also direct reference checklists to be done by memory if no hazard is created by such action, or if the situation does not allow reference to the checklist"
