I think the reason this film received a lot of bad reviews was because Mel Gibson was in it. If Arnold had starred in it--and about 45 minutes were whacked--it would have been much more forgiveable (though a Charlestonian plantation owner--err, make that landowner--with a German accent might have been hard to explain).
I like Mel Gibson, and for Braveheart I'll forgive him a lot. But after being a voice in Pochahantas and now making the Patriot, Gibson surely has set the record for an Australian doing the most damage to American history through film. No, the trees didn't talk to John Smith, nor were the British basically German SS who preferred red to black. And that's where I think being Mel Gibson hurts.
It's okay for Arnold or Jean Claude to have a film in which such niceties as historical accuracy matter not at all, but audiences probably expect more from Gibson. (A nitpick: in the scene in which Gibson almost singlehandedly defeats a squad of British regulars a la Arnold in Commando, why not have him use a bow and arrow? That would have been much more believable than reloading his flintlock after every shot and still managing to defeat 24 men who never bother to seek cover or charge him).
I've had to sit through enough over-the-top portrayals of "us" as the bad guys (Dances with Wolves comes to mind), but I still have a low tolerance for such cheese-cake even when it ought to appeal to the non-PC like myself. The film is way too long, way too predictable, and there's a reason you think you've seen it before: you have...and done better and by Gibson himself, only in a different setting.
An okay movie, but I'd rather watch Braveheart a second time as see The Patriot once.