Lightnix really did alert me to the fact that the third HoL reading was this Thurs - and I have emailed a pile of lawyers at least some of whom have gone off deep 6 at a suitable peer.

The problem IMHO is not that a burden is defined (or otherwise) it is that the minister may do what he considers fit to remove what he considers a burden, unless he considers it is a constitutional matter - all matters of the minister's unfettered discretion!

In any event "burden" is so widely defined that the minister might at one stroke remove all workers' rights and still fall within the definition of "burden" if anyone was empowered to adjudicate whether it did.