THERE is a hidden trap for all Scottish Secretaries during their monthly question session in the House of Commons.

This duel with Scottish MPs has a glamour slot in the House of Commons scheduling, occurring just before Prime Minister's Questions (PMQs).

This can have the happy consequence of ensuring rather a better turnout of MPs than might otherwise be expected.

But it can also create a rather delicate downside. As the Scottish Secretary gets closer and closer to his final question, the government front bench gets fuller and fuller with cabinet ministers arriving for PMQs.

Thus did Alistair Carmichael end his first session as the new Secretary of State for Scotland by sitting down and appearing to perch on David Cameron's lap.

He is not the first cabinet minister to find himself struggling to get a seat somewhere between the Prime Minister and George Osborne, it has to be said.

His predecessor Michael Moore occasionally had the same problem.

MPs from all sides were keen to praise Mr Moore yesterday for the contribution he made in his previous role.

Labour MP Jim Sheridan said that he welcomed the new Scottish Secretary and wished to "send best wishes to his predecessor, a thoroughly decent man".

That view was echoed by Mr Carmichael who said that Mr Moore, sitting a row behind him in the chamber, had done an "excellent job".

For his first Scottish Questions, the Orkney and Shetland MP struck a notably conciliatory note towards the political opponents sitting opposite him, emphasising the case for working together.

He seemed genuinely pleased to be greeted by SNP MP Angus MacNeil as a fellow islander.

But he could not keep his reputation for plain speaking entirely under wraps.

When asked by Mr Sheridan if he would ask his colleagues in the Treasury to review the position on air passenger duty, he said it was a matter for the Chancellor of the Exchequer "and the hon. gentleman should get his representations in early ahead of the autumn statement".

"Good luck to him," he added, with a hint of a twinkle in his eye.