The Glasgow numbers were interesting. Back when I was a lad in short trousers and a BR payroll number, I was given a task of surveying every London-Glasgow day train on the WCML to count passengers (we were checking ORCATs because Intercity East Coast were trying it on).
Delving deep into the memory banks from 26 (gulp!) years ago, I seem to remember the average was around 50-70 London to Scotland passengers per train. This was with about 8 trains a day each way. Therefore in the intervening quarter of a century (double gulp), knocking an hour off the journey time, doubling the frequency and reducing the real price of average fares has more than doubled passenger numbers. Feels about right.