I'm working in London and living in Edinburgh. Have been for more than 2 years now.
Until the beginning of the year I commuted with BACon via LCY. Typical routine:
Monday morning: 6:15 alarm, 6:45 taxi, 8:00 flight, arrive in (Central) London office 10:45
Friday evening: leave office 1400; 1600 flight; home by 1830
Time door to door (assuming no delays): 4 hours. Typical cost: around £240.
My routine now is:
Monday morning: 5:00 alarm, 5:30 taxi, 5:50 train from Edinburgh. Arrive in London office 10:30
Friday evening: leave office 1415: 1500 train; home by 1945
Time door to door (assuming no delays): 5 hours 30. Typical cost (1st class): around £240.
So if it takes 1 hour 30 more, why do I take the train ?
1. I have internet access on the train - it's slow but I can carry on working throughout the journey
2. Can make phone calls (quietly in the vestibule ends, obviously

)
2. I can get up and walk around at any time
3. Can carry whatever sized luggage I like
4. Don't have to strip to my underpants, or leave behind bottles of liquid before I board the train
5. Don't have to sit in a crowded departure lounge
6. (Secondary reason) Following the BACon sell-off I made a policy decision to spend less of my company's money with BA because of the way it treats its non-Heathrow based staff or customers.
If I'd been flying via Heathrow or Gatwick, the time differential would be even less - and the scope for delays even more. So for domestic business travellers, as the rail network is upgraded and trains are improved, and in parallel airport delays and security requirements make transiting airports more time-consuming, travel by rail is becoming more and more a viable option.
I accept that for leisure travel it's maybe a different story. I guess people are more willing to put up with delays/hassle etc. if it's only once a year / every few months.
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