Minnesota Gov. Mark Dayton announced this month that he’ll visit two mining sites suggested to him by supporters of the proposed PolyMet mine as well as two mining sites recommended by PolyMet opponents.

Give the governor credit for doing his homework and due diligence as a lengthy environmental review wraps up and as the permitting process inches closer for PolyMet’s proposed copper-nickel mining operation near Babbitt and Hoyt Lakes.

Give him credit, too, for recognizing that whether PolyMet comes to fruition “will be the most momentous, difficult and consequential decision I’ll make as governor.”

But can apples-to-apples comparisons be made? The geography and geology at the PolyMet site are unique. There’s no other spot like it on Earth, the company and proponents of the project have said. Can visiting other mines provide insights? Can they guarantee or even suggest PolyMet’s success or failure?

“Every operation, every deposit, every one’s mineralogy, every one’s geography, it is all different. So I’m not going to say one or two mines are the definitive compare-contrast opportunity,” said Frank Ongaro, executive director of Minnesota Mining, the state’s copper mining trade group.

Which doesn’t mean visiting other mining sites and gathering information isn’t valuable. Such research can be encouraged — as long as the uniqueness of the different places and the limited insights to be gained are kept in mind. And as long as the visits are only part of the factors weighed during decisionmaking.

The governor doesn’t directly sign off on PolyMet, the environmental review of its plans or even whether permits to mine are granted. The federal Environmental Protection Agency and the Minnesota Department of Natural Resources are among those responsible for that.

However, as Dayton’s office is quick to point out, DNR Commissioner Tom Landwehr works for the governor. Any notion that the governor wouldn’t interject himself into something so potentially transformative to the state would be naive. Of course the governor will be involved. Minnesotans had to expect it.

As long as they don’t cost state taxpayers an exorbitant amount in travel expenses, the governor’s planned fact-finding trips can be welcomed. The information he’ll gather can prove valuable. As long as he and everyone else keeps in mind that experiences elsewhere don’t necessarily guarantee success or failure here.