I remember a lot discussions after 9-11, most were, should we or should'nt we lock the door. I used to fly with the door open also during taxi and almost all cabin crew liked it. But most cabin crew also like that the door is now locked, they are very aware that we are not supermen, that will come rescue them if a highjacker put a knife to their throat. The reason for this is that the cabin crew knows that the potentional highjacker knows that is how it is.
The determined, with no regard for him self and anyone else, highjacker is offcause harder to to deal with and carefull considderation, about how to deal with such a sitiuation, should have been done by all flightcrew.
What I'm saying is that comen rules makes procedures simple, but I'll give you, it's stupid that crew can not sit in cockpit jumpseats.