Anti Skid is right but, only to a degree.
There are no "bonding" agreements on the railway as yet - but they're coming soon.
Virgin Trains have no problem recruiting Drivers from other companies for two reasons -
1st, Drivers want to drive bigger and faster trains.
2nd, The salary and conditions are some of the best in our industry.
The problem is, we have a gentlemans agreement (between most of the passenger companies) not to deliberatley poach existing (qualified) drivers. I took 12 men in one day out of the local train train operating company in Leeds only to find my train home cancelled due to a staff shortage!!
Therefore the main reason for the high salary is due to the fact that it takes 12 to 15 months to train someone "off the street". ASLE&F are also quite a powerfull union - with majority membership throughout the country - and when they say stop EVERYTHING stops.