[itsoktocry]

>Data is useful for proving my decisions once I have made them

I can't figure out what this means, but I have a feeling it's the exact opposite way you should be incorporating data into your decision making.

[corrral]

I took it as:

Prove (?), v. t.

1. To try or to ascertain by an experiment, or by a test or standard; to test; as, to prove the strength of gunpowder or of ordnance; to prove the contents of a vessel by a standard measure.

Thou hast proved mine heart. Ps. xvii. 3.

(Webster's 1913)

Which makes sense to me. Try something you think might work, then test it—is just plain old experimental science.