I’m sure the architect would be mortified by this assault on his/her design.
I wouldn't feel too sorry for them. Am I correct in remembering comments by others that the footbridge design allowed in rain and wind? Was that ever rectified?
No it wasn't - and won't be unless somebody has several millions to spare.
If the space is enclosed it comes under a whole new set of fire and escape regulations - and to meet these requires £££. At the moment it is treated as some form of open space (I don't know the exact regulations) and therefore does not need the extra escape passages and so on which would otherwise be necessary.
The openness of Reading overbridge concourse was done for the same reason for the openness of Blackfriars and London Bridge. It was explained to me by a Civil Engineer who was involved in Blackfriars and Farringdon the main concern is in the event of an IED exploding the pressure from such a device would cause a much higher number of casualties in an enclosed space, there was also the consideration as mentioned of a fire and the need to vent smoke.
Stations are designed for the free flow of people the most important time is in an emergency evacuation