The world No 1, like all Northern Ireland athletes, can choose between representing Team GB or Ireland – and, having seen the reaction last autumn to him saying he felt "more British", McIlroy (pictured below) has even said he might not to go to Brazil at all such was the ferocity of the reaction in certain parts.
Dubliner Harrington, in South Africa for this week's Volvo Golf Champions, said: "I have massive sympathy as an Irishman and massive sympathy more so as a sportsman.
"No sportsman should have to make that decision. That's it, straightforward – nobody at 23 years of age should be asked to make that decision.
"The reality is that there have been people in politics for the last 100 years who have tried to negotiate that and haven't been able to. So, why would you ask a 23-year-old just because he's going to hit a little white golf ball?
"It's very unfortunate in the sense that it means a great deal to golf for him to play.
"It's a very big deal because golf (not part of the Games for over a century) is only on a trial period in the Olympics.
"We have two runs at it and we do, as golfers, have to perform and put our best foot forward, so it would be nice if the world No 1 was there supporting the event.
"It's an extraordinarily difficult decision. We need our best players to play in the Olympics to show that golf is serious about the Games.
"It would be nice if the Olympic council would say: 'Here we go, you can play in the Olympics,' or make the decision on a player's behalf.
"There's going to be no winner out of this one whatever."
Seventeen years on from making his professional debut on the European Tour in the FNB Players Championship, Harrington returns to Durban Country Club for this week's Volvo Golf Champions event.
Despite playing "terribly" from tee to green, the three-time Major champion finished in a tie for 49th place in a tournament won by Wayne Westner – a result, which helped convince Harrington he belonged on the European Tour.
Fast-forward almost two decades, and Harrington has racked up 14 titles and accrued more than €23m in career earnings on the European Tour.
His last Tour title came at the 2008 US PGA Championship, since when Harrington has struggled to recapture the form of his halcyon days. But the Dubliner has high hopes for the 2013 campaign and is itching to return to competitive action after six weeks away from the game.