By Nyta Mann BBC News Online political correspondent

Conservative leader Iain Duncan Smith's compromise over repealing Section 28 is, according to a random straw poll of Tory MPs, "messy", "a camel" and even "illogical".

Maybe so. But it is still far less messy than last autumn's almighty row over gay adoption.

On that occasion, Mr Duncan Smith's insistence on a three-line whip against allowing unmarried couples to adopt sparked chaos in Tory ranks, culminating in his desperate appeal to his party to "unite or die".

The debacle highlighted just how fragile his grip on his own party is and cast a harsh light on his judgement, after 35 Tory MPs - including shadow cabinet members - refused to toe the line on what they saw as a litmus test of their leader's commitment to modernise.

By allowing his MPs a free vote on Section 28, Mr Duncan Smith hopes to avoid a repeat performance.

But it comes at the cost of appearing to be all over the shop.

Free vote

For a start, it is hardly usual to table an amendment, as the Tories are doing for the Commons debate to scrap Section 28, only to declare that their own MPs can vote however they want on it. Where is the logic in that?

David Davis: Presented the compromise to the shadow cabinet

Shadow deputy prime minister David Davis - reputedly the driving force behind imposing the three-line whip on adoption - insists the amendment is needed because "our number one priority is to offer children genuine protection".

This is exactly the same line that was trotted out in defence of the party's stance on gay adoption, yet this time MPs will not have to back the "number one priority". Where is the consistency in that?

Frontbench not consulted

Meanwhile, if Mr Duncan Smith hoped the compromise would serve to avert ill-feeling among his own troops on the issue, he has already failed completely.

The amendment was suddenly presented to the shadow cabinet by Mr Davis at its regular Wednesday meeting. There had been no prior consultation with frontbenchers or even soundings-out by party whips.

The first shadow spokespeople heard of it was from Westminster journalists - something politicians hate almost as much as journalists love.

Iain Duncan Smith is a leader who knows he is not expected to make it beyond May. It should come as no surprise, then, that the approach to repeal Section 28 is as much about his own survival as it is about the issue itself.

But while the compromise he has stitched together may succeed in avoiding a leadership crisis along the lines of last autumn's shambles over gay adoption, the odds of disaster further down the line remain altogether unchanged.