Let's get the facts straight here: the 767 on the taxiway had quite the string of problems and a pretty bad case of fatigue before putting it on the taxiway. There had been numerous other attempts to land on the taxiway under those lighting conditions and sidestep conditions, so obviously there were more factors at play. It absolutely doesn't excuse them, but there needs to be an understanding of what happened. There was a major reason they were allowed to keep their jobs. Tower noticed them about to touchdown on the taxiway and let them land there after scanning and checking for anyone on the taxiway. That alone is a bit scary.... anyhoo....
Now then, this PSA crew displayed a significant lack of procedural maturity. There is some understandable shock involved in the post wreck stuff, but leading up to that point, come on! Just on the takeoff roll: 1. moving the flaps on the takeoff roll after realizing there is an error. 2. not understanding that when you take the flaps inbetween settings the config alarm is going to go off. 3. going against the hundreds of lives already lost in high speed aborts and aborting WELL above V1.
As far as performance stuff, it is very very simple to not jack up variable flaps settings... we use 5, 15, and 20 on the 767 and 757. About 80% of the time we use Flaps 5 which produces V-speeds in excess of CRJ flaps 8 speeds. The book procedure is on the salute to select the flaps setting from the data, and then during the checklists verify lever position and indication.
For technique augmenting our required procedure, on the checklist call I point to the data for the flaps setting, move to the indicator and verify, and then physically grasp the handle and verify it's position again. We do that check twice- once in the taxi checklist and once in the before takeoff. You use that technique combined with the double checks and you will never jack up the flaps setting.
The reason for the double checks are both the NW MD-80 back in 1986 and the DL 727 in DFW in 1987. Let's respect the dead and not make the same mistakes that have already killed hundreds....