After a difficult start to the season for himself and team-mate Sergio Perez, McLaren is pinning hopes that a raft of developments being introduced at Barcelona will help it make progress.
But rather than head to the start of the European season full of confidence about what is coming, Button said on Friday that he is keeping his feet on the ground, and accepting some parts may not deliver what was hoped.
"It's been difficult for the team to make consistent progress through the first four races, but I think returning to a circuit where we undertook two of the pre-season tests will give us a useful benchmark of our progress so far," said the former world champion.
"There's been a lot of talk about the importance of next weekend's upgrades; but, as with every upgrade, they're simply part of the series of continuous improvement that are made across the season.
"As always, there'll be elements of it that work, elements that perhaps work in a different way to what we'd anticipated, and elements that don't work, or perhaps require further work. That's life in modern Formula 1.
"So I'm pragmatic about what we'll discover next weekend. Of course, I'm hopeful that it'll move us a step closer towards the destination."
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