a voice piped up and said 'Nigel - either sh1t or get off the pot"
I have
got to find an opportunity to use that one!
Sometimes controllers get it wrong. I was once severely reprimanded by a DUB ATCO on GND frequency. It was completely inappropriate, partly because the controller was utterly mistaken and misinformed but also because of the patronising language he used on air. I was polite despite feeling aggrieved.
I'd say the DUB controller in this case sounded a bit stressed but that doesn't excuse a professional flight crew from accepting a line-up clearance when unready. Nor do the delay tactics paint them in a good light. They should have told the controller they needed a specific amount of time and if that wasn't possible due to the overall ATC picture, they should have vacated immediately.