They gotta change up history to produce a better movie.. and, yeah, you're ALSO right about your thoughts that maybe they didn't get details right, but the overall message taught us a few things we might have otherwise never known..
There are a LOT of goofs in Braveheart.. I kind of like finding the goofs..My favorite is during his wife's funeral.. Now, depending upon what version you are watching you may or may not see this: During the funeral, in the far background, a white van drives through.. They removed the scene later on for TV and whatnot, but its on my DVD..
My other favorite goof is right at the end of the first battle - Stirling.. Mel Gibson yells something and they pan to the guys still in the field.. way in the back, there is a guy with a sword about to smack the snot out of a guy with a shield, I think.. Anyways, somebody must have yelled "cut" because he very lazily and slowly kinda taps the guy's shield or sword - can't remember which - that he's fighting and then they both stop.. Kinda funny...
Friendship is like peeing your pants.. Everybody can see it, but only you can feel the warmth..