there are two ways to look at this
you have the old system which was basically a minumum wage and union action whenever a dismissal took place
so this was like having a price floor in the labor market - so you would have supply and demand for labor and then a floor price fixed that is above equilibrium - this acted to prevent the minimum wage from falling, and inflated the price of employment to the point where there was excess supply and diminished demand
so basically more people want work, and at the same time employers want to hire less
this was pretty bad policy on a number of levels because it means that the economy cannot adjust to shocks to aggregate demand through wages and incomes policy since the minimum wage is fixed so a negative shock would result in unemployment as the minimum wage cant adjust to lower to keep people employed
so under the new rules - which then went backwards due to the fiarness test hence sorta making them a minimum wage again (although more flexible and still lower than the previous miniumum wage) - the costs of employment have fallen, hence there is greater demand for employment so there is a rightward shift of the demand curve - or there could be a lowering of the minimum wage - depending on how u argue it
or it could be a combination of the both - obviously this policy has the desired effect of reducing unemployment
another way it increases employment is increasing the demand for part time workers through flexible working hours
anyway thats the economic theory behind it, again it's subject to political spin so i would be careful what i write - prolly ur best bet would be to go, this is what it is aiming to do, but then question whether it actually has done that and both parties would be pleased i guess