Northern Light
Superstar
As I have said here before (or, at least, thought of saying!) PEDs are certainly VERY desirable at busy stations like Bloor-Yonge or stations with very narrow platforms. They may also be good in every station, eventually. It is quite possible to install them station-by-station so that we can learn from experience of problems and solutions. (Though I am sure that if some stations got hem and some did not there would be the usual accusations of discrimination!) The doors do not need to be the same at every station, some may be best 'full-height' (which is probably the gold standard), others may only require waist-height doors - which would also reduce the problems of ventilation in older stations - full-height doors would require major ventilation changes in many stations. In short, if one wants to lobby for PEDs then lobby for a gradual approach that can be varied as station architecture and crowding and experience dictate.
Note:
1) 1/2 height doors do very little on the subject of litter and thereford attendant fire/smoke related delays.
2) The estimates I offered for the cost of installing PEDs include ventilation upgrades; and to my understanding, are based on a full-height system.