Before Karl Rove was questioning Hillary Clinton's viability to enter the 2016 presidential race given her health and age, he was expressing outrage at Democratic political operatives who examined the age of an even older presidential candidate.    

When Sen. John McCain (R-AZ) was battling Obama for the presidency in the spring of 2008, he was 71 years old. At that time Rove told Fox's America's News HQ that it was “reprehensible” to suggest McCain's age was a liability (emphasis added): 

HEMMER: All right. Let's shift our focus now to John McCain. Howard Dean and the DNC is circulating a rather extensive study that they have done in 17 different swing states across the country and they conclude that the age of John McCain is hurting him with some of these moderate voters. What is your take on that as they take on McCain?

ROVE: You know, look, I think this is really reprehensible on Dean's part. First of all, I don't accept the argument because if Senator McCain were having a problem with independents because of his age, he would not be tied or slightly ahead of or slightly behind either Clinton or Obama in all of these national polls. In fact, right now, he should be way, way behind both Obama and Clinton and he's not. In fact, he's ahead of them in most of the national polls.

And, I think, this is really - I mean, the Democrats have done this before. We saw this drama being played out and their story being spun out on the same way in 1979 and 1980 when Ronald Reagan was on the ballot. And I think, it's going to probably be as unhelpful to Democratic cause again this year.

Fast forward six years to Rove justifying his speculation that Hillary Clinton may have suffered a traumatic brain injury in a 2012 fall by suggesting it's customary to question a potential presidential candidate's age and health. From America's Newsroom on May 13 (emphasis added): 

ROVE: My other point is, this will be an issue in the 2016 race whether she likes it or not. Every presidential candidate is asked for all of their health records, by The New York Times, they turn them over -- and vice presidential candidates -- they turn them over to a battery of doctors and they examine them in detail. And my point was, that everybody says she's going to run and she probably is. But I would bet it's a more complicated calculation than we might think because, look, she'll be 69 by the time of the 2016 elections. She will be 77 if she serves two terms. And this ends up being an issue. I would remind you, John McCain - here's the headline from U.S. News and World Report: “McCain's age and past health problems could be an issue in the presidential campaign.” This happens every presidential campaign.

[...]

When you go through a health incident like this, any presidential candidate, any presidential candidate has to ask themselves, am I willing to do this for eight years of my life, serve? And run for two years and then serve for eight? And particularly when you're, you know, it's a natural thing to say, when I'm 69 years old, 77 -

HEMMER: I think that's a calculation for everybody. Quickly -

ROVE: Yeah.