On the face of it, Britain and Lesotho are very different places. One is a small, landlocked, impoverished African country with an average life expectancy of fewer than 35 years and a rather inconsistent record on democracy. Britain, in theory, is a much more sophisticated nation. Yet we share something in common.

We are the only two states where seats in the upper house of a parliament are reserved on a hereditary basis. In Lesotho, two thirds of the Senate consist of the “Principal Chiefs” or “sons of Moshoeshoe I”, a king from the Victorian era who sired a host of male heirs. The other third are appointed at the behest of the ruling party. Britain's arrangements are only slightly less anachronistic. Some 85 per cent of the House of Lords consists of those nominated courtesy of Principal Chief Blair (including the preferences of the other party leaders), about 12 per cent are hereditary figures and the rest are Anglican bishops.

This alone would suggest that comprehensive reform of the House of Lords is about a century overdue. But it has been almost a century since that process started and it has not, in truth, made much progress. Until 1999 most of those in the second chamber were there as a result of an accident of birth, something that schoolchildren today will find impossible to believe when they are adults. That anyone retains a vote in Parliament because their ancestors won (or bought) the favour of monarchs long dead or prime ministers of yesteryear should be a matter of immense collective embarrassment.

This week the House of Commons will embark on the latest attempt to rectify (or not) this situation. It will do so in the manner of one of those television quiz programmes that have been condemned recently by regulators. These consist of starting with a really easy question (what is the capital of France?), moving on to a slightly tougher one (what is the oldest cathedral in Paris?), shift gear to a much harder one (the year in which Notre Dame was founded?) and, finally, the stinker (how high is its central spire?).

So, in the same spirit, MPs will be compelled to address up to nine different questions. First the simple stuff; should there be an Upper House, followed by does it need reform? Having answered these in the affirmative (presumably), the House of Commons will move on to a cross between the Eurovision Song Contest and Russian roulette. Namely, whether the elected component of a modernised second chamber (minus hereditaries) should be 0 per cent, 20 per cent, 40 per cent, 50 per cent, 60 per cent, 80 per cent or 100 per cent?

To put seven options in front of MPs is a recipe for chaos. Last time they were given a multiple choice, by the late Robin Cook in 2003, a clear majority of the House voted for a proportion of the House of Lords to be elected — but they could not reach a consensus over what that number should be. As a result, every one of the seven possibilities failed to secure the necessary approval.

It was legislative slapstick. It could be even more risible this time. For it is perfectly possible that MPs will overwhelmingly endorse the motion that the House of Lords should be overhauled and then, once again, be incapable of finding a final formula between election and appointment.

That would suit the House of Lords fine because the life peers have no intention of allowing anything as vulgar as elected people to come between them and their Central London parking places and amiable alcohol establishments (and I have to acknowledge that you do meet a better class of drunk in their lordships’ hostelries). For these “lifers” (not in the HMP Wandsworth meaning of that phrase, where many of the residents are released early) the 92 hereditary Lords are useful human shields because they could be sacrificed to demonstrate that change had occurred but without endangering the essential status quo.

This is an absurd position to be in. That it persists after a decade of Labour government is surreal. And in their hearts even those at the core of the establishment know it. Lesotho is, after all, the only one of our former protectorates to adopt a variation of the House of Lords model and before it became independent 40-odd years ago Britain sought to talk the new nation out of the scheme (although since more than two thirds of our own Upper House at that time consisted of hereditary chieftains, this was slightly hypocritical).

For sanity to prevail, MPs who want a substantial elective element have to stop engaging in mathematical perfectionism. Mr Cook’s efforts were sunk because those who favoured a 50 per cent elected Upper House would not back 80 per cent and vice versa. The result of their behaviour was zero per cent elected and 92 hereditary peers left intact.

Personally, I would endorse a simple 50-50 split between those chosen at the ballot box and others appointed on the basis of expertise, not because they were in the Cabinet once (spare us Lord Milburn of Tight Jeans), financial donors or authors of awful novels. That 50-50 divide is being championed by Jack Straw, the Leader of the House of Commons.

He has said, however, that he would back 60 per cent and 80 per cent if his preferred 50 per cent figure was not accepted. So would I. It would be better for one of the serious reform proposals to acquire a majority than have none of them do so. For should the House of Commons make a hash of it again on Wednesday and Thursday, it could be a further decade before another determined drive to create a credible second chamber is initiated. By then, to our enormous shame, Lesotho might have imposed an elected element on its Senate.

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