Given that this has cropped up on here a fair bit this year, it seems to be a concern for a number of First travellers. I had a CEO who always said that if you wanted to do something, really wanted to do something, you would find a way. The rest of the time, you find an excuse.
The First product from T3 is inferior to the T5 product. If BA "really" wanted to add further value to the First product from T3, is it really beyond them to allow all F passengers to enter T5 to use the CCR and then use the Jaguars for an air side transfer direct to the aircraft? I imagine most would not take them up on it. Perhaps it could be a booked service similar through You First, similar to booking an Elemis treatment.so demand can be managed. It may even be a precursor to a full on LH ,model of this service for all First passengers. On BA, from lounge to aircraft is a weak link in the First product in most airports, especially the home bases.
As I said, it seems to be important to a number of First passengers flying from T3. If BA "wanted" to do it, I am sure it is not beyond the wit of invention.