The phrase "agreed about how" is correct and usable in written English.
It can be used when discussing consensus or mutual understanding regarding a method or approach to a particular issue.
Example: "After much discussion, we finally agreed about how to proceed with the project."
Alternatives: "reached a consensus on how" or "came to an agreement regarding how".
All the same, not everybody agreed about how big that bounce would be.
But a month before the premiere, Ms. Monk and Ms. Hamilton hadn't agreed about how these individuals should appear in the piece.
The ministers have not yet agreed about how to structure the aid, and Mrs. Merkel's statement on Wednesday seemed to suggest that European leaders were interpreting the aid promise in different ways.
The experts above may have agreed about how serious the problem of personal privacy is, but solutions are harder come by.
There is little evidence of sustained settlement in the area during the Bronze Age, but from excavations of hill forts it is clear that there was some Iron Age occupation, circa 500 BC, although scholars are not agreed about how permanent it was.
At the time, few agreed about how profound the change would be...that smartphones would go from the third to the first screen, that we'd rely on these devices for so much of our daily lives, that mobile was not a channel but a lifestyle, that consumer "moments" would be at the core of the smartphone experience, and that brands needed to take a holistic approach to mobile or risk irrelevance.
(In Ms. Galinsky's study, the only thing that parents and their children agreed about was how often they watched television together).
After all, we're already no longer able to agree about how to know.
And the airlines do not agree about how traffic levels may be cut.
But Kitcher suggests that religionists and secularists actually agree about how to create meaning in a life.
Not all strategists agree about how to interpret this information, but the source of the data is no secret.
