Chris Wilder believes it is one of the biggest myths in football. A charge levelled at managers by amateur tacticians whenever something goes wrong.
On several occasions this season, despite finding themselves second in the Championship, Sheffield United have also been accused of lacking a 'Plan B'. Much, their manager has admitted, to his own bemusement.
"Personally, I think all that stuff is a bit of a nonsense," Wilder said. "My response, whenever anyone asks me about it, is thaty I'd rather be good at 'Plan A'. That's the plan I'm bothered about.
"In any case, you can't do well on a consistent basis if you aren't flexible. Like everyone else, we are capable of changing it about."
Winning football matches is something Wilder has excelled at since being appointed, after leading Northampton Town to promotion, 32 months ago. Indeed no one has won more, in the top four divisions of English football, over the past three years.
With nine home games remaining following Saturday's meeting with Queens Park Rangers, Wilder suspects United's strategic powers will be tested to the limit between now and the end of the campaign as the race for automatic promotion and play-off qualification gathers pace.
"What we do at our place is going to be absolutely crucial," he said. "From here on in, and every other manager will tell you the same, the home form is going to be key. Every time you set foot on the pitch, it's important. But there aren't too many people who achieve something without being strong at home."
"I think what you're going to see from now on in, particularly when they come here, is teams sitting in and looking to make it really difficult," Wilder continued. "There's going to be exceptions but, for the most part, I think we'll see them tucking in."
Although that hunch will not persuade him to ditch the 3-5-2 system, including attacking wing-backs and over-lapping centre-halves, which has proven so successful, it could see United showcase some variations on the theme.
"We're not looking to take our foot of the gas, stop being full tilt, front foot or any of the other silly phrases I come up with," Wilder said. "Some clubs will tail away. Others will play with a heavy shirt. Here, we're just looking to soak it all up, keep doing what we're doing and make sure we enjoy it."
One of those potential deviations is a midfield partnership involving Mark Duffy and Kieran Dowell. Although Dowell was signed on loan from Everton to provide competition for the 33-year-old and replaced him during the closing stages of the win over Rangers, Wilder has admitted coaching staff are investigating the possibility of playing them together if the situation demands.
"It's not necessarily a case of one or the other," he said. "There's no reason why Duffy and Kieran can't be a 'two' if we think that's best for a certain match or part of it. They're intelligent professionals. It's something we'll look at in training."