There was a lot of friction in PMQs today, even though the subject under discussion was less friction, or ideally no friction at all.
Yes, we were back to Britain's borders after Brexit which Jeremy Corbyn sought to weaponise.
And that created much friction on the narrow House of Commons border which separates the Tory benches from the Labour ones.
Mr Corbyn's first question was a humdinger. Whether Theresa May's declaration that she wants as little friction as possible applied to EU trade or her next Cabinet reshuffle.
Even Mrs May found that one funny.
The Labour leader then wanted to know how much friction she would accept. Mrs May repeated: "As frictionless as possible."
And her non-answers kept coming.
She said: "This Government has a policy..." and the rest of that sentence was lost in raucous laughter. A policy is one thing she doesn't have.
Mr Corbyn asked how many more customs officers Mrs May was hiring given the Dutch are on a recruitment drive just to deal with British goods.
Mrs May dodged that one.
Then Mr Corbyn launched his tour-de-force. Mrs May should step aside and let Labour take over the negotiations.
Her reply was lost in the uproar from both sides of the House.
Former Cabinet minister Owen Paterson rose to his feet, his head balanced on a neck brace following a broken back from a riding accident.
He attempted to stiffen Mrs May's resolve to have no truck with the EU's single market or customs union.
But until he makes a full recovery perhaps he was not the best person to strengthen her backbone.