Have we lost track of the government’s Health Bill, which has turned out to be not the promised “flagship” piece of legislation but a “rather small” boat, as Andrew Lansley joked during its Commons second reading?

In all the excitement at Westminster over expenses and Gordon Brown I certainly did. So did MPs. On the night of the second reading debate (the Tories did not vote against) a single Labour backbencher was present at one stage: all the others were at that crucial meeting which saved Brown’s premiership.

Since when it has been racing through its detailed committee stage, a process which has revealed a new burden for the Hansard shorthand writers: new health minister Mike O’Brien has been squaring off on the new NHS constitution and other matters, with his Tory shadow Stephen O’Brien.

Both MPs are lawyers, though neither has practised lately, and talk lawyerese. SOB (as I must call him) pressed MOB hard on the constitution, which has been both supported and roundly condemned as neither fish nor fowl (“I do not know what it is, but it is not a constitution,” observed Lib Dem health spokeswoman Lady Barker).

Is it justiciable, in the sense of allowing the NHS to be taken to court to enforce new rights, asked SOB? In theory, the answer is no.

Ministers “want to avoid large scale new legal action… we already have enough,” replied MOB who spoke (as health secretary Andy Burnham does) of the need for balance.

The bill consolidates existing rights; adds that odd trio of rights to choice, vaccination and National Institute for Health and Clinical Excellence recommended drugs and treatments; and not much else. As a constitution sceptic who sees it as waffly window dressing I still suspect the lawyers will have a field day. The constitution actually only applies to England, though the devolved Celtic regions have promised to follow its spirit: a promising dog’s dinner. Never mind. The new health secretary is not only a supporter, but was the idea’s champion long before Lansley and David Cameron took it up, so he insisted in the Commons debate.

The constitution is not actually in the bill (to help keep the lawyers at bay). Nor is it arguably the bill’s most important bit.

Remember, the bill also creates a duty on trusts to provide annual quality accounts; allows for personal health budget pilots; brings in prizes for innovation; allows Whitehall to intervene faster against failed trusts (and primary care trusts against failed pharmacists); sends the local government ombudsman into private care homes and further curbs tobacco advertisements, a change which disproportionately enrages libertarian peers and MPs.

I am still struggling through the committee stage debate. But peers imposed a significant change when they voted to ease foundation trusts’ private income cap (provided they benefit the NHS). This change had all-party support, including Labour’s ex-health minister, Stormin’ Norman Warner, who helped junior minister Burnham impose the cap in 2003 - only to watch it later damage foundations: “I repent my sins,” Lord Warner told peers.

At Commons second reading, Handy Andy signalled less than outright hostility to the peers’ move and promised to consult widely. He also had sharp exchanges with Mr Lansley over Tory plans to abolish targets, including the maximum four hour wait in accident and emergency.

If I understand Mr Lansley correctly, he is trying to differentiate between response times appropriate to, say, minor accidents, and stroke. In what he calls the “real world”, targets distort them. Expect to hear more about this as the election looms.