Plumbers doing poetry

From the Scotsman:

Jack McConnell signalled his determination yesterday to take on Scotland's teaching unions when he announced plans for vocational trades academies in every region.

Despite fierce opposition from Scotland's biggest teaching unions, the First Minister used his speech to the Labour Party conference in Manchester to unveil proposals for 100 "skills academies" across Scotland.

Under these plans, non-academic pupils would be diverted at the age of 14 into special units to learn more traditional manual trades like plumbing and joinery."

Hmmm - we don't know the details yet but unlike our union representatives I think you'd probably find that most teachers would think something like this is a good idea. Vocational education is famously neglected in this country and most teachers will tell you tales of the misery that is imposing a one size fits all academic curriculum on pupils who simply aren't interested. The unions don't agree. David Eaglesham of the SSTA said,

"This is all about election posturing and not about education. It is the worst form of selection. It is an arbitrary process. You are doing these kids down in a big sense. There is no reason why plumbers shouldn't do poetry."

I don't understand this - why would this form of selection be worse than selection by ability or income? There is indeed no reason why plumbers can't do poetry but is there any compelling reason why they should have to do it if they don't want to? No doubt in theory there is - but in practice we can see none.