Rob Roy McGregor really existed and probably was a "larger than life" character, and indeed I have visited his grave in Balquhidder church yard.
Probably the tales of his exploits were exaggerated as they were repeated and much of his life story his been fictionalised by writers such as Daniel Defoe and Sir Walter Scott and more recently by the film (movie).
Much of his true life story will have been lost to history but perhaps this link conveys a more accurate picture than the public perception.
http://www.undiscoveredscotland.co.u...macgregor.html