Simple aircraft should equal simple checklists which should be capable of being committed to memory - with no reduction of safety (TMMPPFFISHH?). Old fashioned, complex aircraft have to have checklists because there is too much to reliably remember. For modern aircraft (& I'm not talking about relics like the 737) an airborne checklist is probably not required (because there are so few items) but few have the guts to say so! Why? Because I'm expected to remember 19 Memory checklists and spew them out at times of high stress, I can surely remember the eight items (three lists) that make up the entire airborne checklist.