it never takes long before silly little put down start hey BOAC...I use the window as an extreme example, but yes you are absolutely right you can exit via the stairs..well done! I drink coffee by the way!
TC I'm a little confused, if they ordered an evac I would have thought that was an indicator of acting with urgency.
I dont know the exact circumstances but with such indications as you have intimated the FD would check that its not a spurious message,check with the cc in question, ATC, firebrigade etc to try and confirm cargo smoke before evac command. It seems in this case a very quick command to evac.
In my example I would expect masks to be put on and await communications from FD once down to FL100 and level. This was an incipient loss so would have crept up on crew, but masks should have been put on as sop's dictate.
A lot of this stuff does rely on good communications between fd and cc. SOP's are there to provide basic responce to a situation. If the cc in question had followed SOP's then all would have been well. I refer back to my worst case scenario