Former Massachusetts governor Mitt Romney said late Tuesday that Marco Rubio is being fully vetted as a potential vice presidential pick, directly rebutting reporting that the Florida Senator was not in the running.

US Senator Marco Rubio, R-FL, waits to speak during a seminar on "Is the American World Order Sustainable and Necessary in the 21st Century?" at the Brookings Institution in Washington, DC, on April 25, 2012. AFP PHOTO/Jewel Samad

The simple fact is that the VP decision is made, typically, by a very small group of people that includes the candidate, his spouse and one or two top advisers. And those people don’t have much incentive to talk about their thought processes with until a decision is made.

Add to that reticence the fact that the VP process is dynamic rather than static — meaning that how it starts is not necessarily how it ends — and you begin to grasp the challenge of reporting on who will be number two. (Don’t assume that Rubio wasn’t being vetted at the start of Tuesday but by the end a decision had been made to do so.)

The examples of feints, false starts and outright swings and misses on the veepstakes are legion. In 2004, the New York Post famously/infamously released a cover that touted then Missouri Rep. Dick Gephardt as Massachusetts Sen. John Kerry’s vice presidential pick. (Whoops!) And, in 2008 no one even saw then Alaska governor Sarah Palin as a short-lister for Sen. John McCain — much less the actual pick.

Given that, why not simply ignore all the VP chatter until the presidential nominee makes his pick? That’s impossible — and shouldn’t be done — for two big reasons.

First, how the presidential nominee makes up his mind on the biggest decision he makes before actually being elected president is critical to understanding how he might govern.

Second, there is massive interest — from political junkies and casual news consumers alike — about who is in the running for vice president. It’s a guilty pleasure that almost everyone indulges in. It’s like “Jersey Shore”. Everyone says they hate it and don’t watch it but Snookie isn’t a multimillionaire because the show gets bad ratings. (And, yes, we just compared the veepstakes to Snooki.)

And so, what reporters (the Fix included) are left with is trying to understand the big picture through the eyes of sources who may have never been granted access to see it. Or who saw a picture that has changed or is in the process of changing even as stories are being written.

What does this mean for readers? That all vice presidential reporting — up to and including what we write about the veepstakes on the Fix — should be taken cum grano salis. What’s accurate one day or to one person’s mind could change at a moment’s notice.

Don’t expect a decline in VP coverage. It won’t happen. But go into that coverage with your eyes wide open about its limits.