A vamp is, of course, a scarlet woman. Peers also favour scarlet - they are given to wearing scarlet robes and sit on benches of much the same colour - but one likes to think that this is the only thing that the two groups have in common. If a vamp is a temptress, a revamp is presumably some sort of tarting up. That's hardly the spirit in which the Commission is expected to embark on its solemn task.
However, things can sometimes turn out to be better than they sound. For there are two kinds of vamp. The one that's to do with predatory women is simply a shortened form of vampire, the blood-sucking creature that exists only in the minds of horror freaks. The other could hardly be more prosaic by comparison. It's an anglicisation of the French avantpied, and means a toecap, or, if I've got it right, the upper part of a shoe.
To vamp something, properly speaking, is to give it a toecap. Or more likely a new toecap (revamp is Victorian, and would probably have been thought tautological in the 18th century). This has also long been a word for any patch-up job. Still not quite what the nation hopes for from the new second chamber, but better than a tart's boudoir.
It's more or less inevitable that this kind of vamp should sometimes get mixed up in people's minds with its vampirish homonym. Dr Johnson wrote in The Connoisseur (not the familiar art-lover's mag, but the one that ran from 1754 to 1756) of "the woman of the town, vamped up for show with paint, patches, plumpers, and every external ornament that art can administer" who sounds fairly like a vamp to me, though he was writing 150 years before this second meaning of the word became current. I had imagined that the said "plumper" was a bust-enhancer. But no, it was "a small light ball or disk sometimes carried in the mouth, for the purpose of filling out hollow cheeks", according to the OED, which cites Dr Johnson as well as Richard Steele in the Tatler ("Two Pair of brand-new Plumpers, Four Black-lead Combs, Three Pair of fashionable Eye-brows ... ").
There is one obvious sphere in which revamp has a perfectly respectable connotation, and this is in the world of newspapers and magazines. The first thing a new editor (or more probably a new designer) itches to do when he or she gets the job is to go for a revamp, and no one thinks the worse of them for this very natural urge. So perhaps, after all, Mr Hennessy was only thinking in the language of the newspaperman when he wrote of the revamping of the House of Lords.