"
Presumably the TriStar fleet has now been grounded until all other doors/chutes have been fully checked"
I hate to say this BEagle, but in the real world ( the one without the RAF chain of command and, at times, self justification structure ) I have deployed several life ex.slides that duly dangled in the metaphorical breeze...never grounded a fleet however. No need.
Good video though....liked the engineers reactions !
Dengue..girt bar...it's a bar that is attached to the slide by a steel cable. The bar is then attached to the cabin floor by the CC prior to push back ( the RAF will probably have totally different procedure of course ) hence the term "Doors Armed" or "Doors to Automatic" and, in theory, when the door is opened" in the unlikely event" etc, the tension on the cable, will result in the N2 bottle inside the slide being activated and the chute duly deploys.
This can be "rather interesting" when Ms Vapid forgets to disarm the door on arrival at an airbridge and the slide deploys as intended...she found it sooo funny....then she had an "educational" meeting with the engineers.