Your fire insurance wont allow you burn down your house in order to get a newer or better house.
Similarly, social welfare insurance wont pay for re-training when you already have a job. You must be genuinely made redundant or long term un-employed.(or disabled or reciept lone parent etc.)
The scheme was introduced (as far as I can remember) on the basis that people would update their skills and would eventually become employable again, thereby saving the social insurance fund money.( & reducing the live register figures).
I know this sounds harsh but its the best way I can explain what I think is the ethic and reasoning behind the BTEA.
I accept that there is anomolies and some people are better at working the system than others and I empathise with your frustration.
Social welfare regulations is like a stone wall imo, its pointless trying to go through them, you just have to work your way around it.