Last year, LeBron shot .8 threes per game less than Kobe and more than Carmelo.
Also, Carmelo was assisted on 90% of his threes in Denver and 77% in NY compared to LeBron's 61% last year. That tells me that most of Carmelo's threes are the open, catch-and-shoot variety, as opposed to LeBron's pull up threes. And that also tells me that Carmelo has plenty of breathing room on the perimeter if he is open so often.