Do you seriously think that the SHAR would offer a defence against an ever present threat? Not with the numbers you could place on a Invincible class. No real chance of holding 'ready 5' 24 hours let alone a 24 hr CAP. We would still need allied assistance which in my opinion negates the whole point of SHAR.
Not really able to answer that, but surely some defence is better than none?
If you seriously think that the USN would not be on station with a large number of AD assets during a hot period with Iran then you are, with respect, not being realistic.
Will they be able to provide continuous CAP? If not, will the USN fighters be able to reach our task group faster than the hostile ones? I am assuming that UK forces operate as a discrete group, possibly responsible for a separate area within the theatre.
What if the solution to a crisis isn't just dropping bombs, but things like mine clearance? Just a few hostile aircraft could cause mayhem.