I guess with most cars out on the roads today having a high level brake light as standard, drivers are being spoilt allowing them to reply on this third light as it's more visible.
The Capri is a lot lower than all these modern cars we see, and I feel the Capri's brakes lights may not get seen in today's modern traffic until it's too late. I thought a high level third brake light would come in handy to avoid getting rear ended, that's my paranoia kicking in.

I guess this effects all classic car owners, I felt the same with my MGB.