I had the privilege of watching Brian Leetch up close and frequently from the time he arrived in the NHL through the late 90s, as I lived in Manhattan during that time, and had season tickets to NYR. (I'm not an NYR fan, but a hockey fan, and MSG was a short cab or subway ride.)
Leetch was as talented an offensive dman as there was in the game from the tail end of the 80s through much of the 90s, especially the first half of that decade. A GREAT passer, he was also one of the dwindling few dmen who could take the puck and rush it from deep in his zone into the offensive end. A great PP QB, with an uncanny ability to keep the puck in on the line. His Calder and Norris Trophies are testament to it.
Up until 1994, he was average to slightly above average in his own zone. Mike Keenan's one season in NY changed that, considerably. He challenged Leetch (even benching him for a bit during a playoff game vs. NJD) to become a complete player, a more aggressive defenseman. By "aggressive," I do not necessarily mean a physical monster, but more assertive in his own end. Keenan believed that Leetch had to raise his level play to that complete elite level in order for NYR to succeed. Leetch did, and NYR won a Stanley Cup, with #2 winning the Conn Smyth.
Post-1994, injuries started accumulating and taking their toll on Leetch and his overall game, clearly. The timing of your post is interesting - just last night I was commenting to a friend that it is sad to see Brian in what is now clearly the twilight of his career. His game is a mere shell of what it once was, and unfortunately, declined a bit sooner than it did for other great dmen of this era, i.e., Bourque, Stevens, Chelios. I would not be surprised if he calls it a career after this season, though as a fan, it would be sad to see the end of a special career.
To answer your question directly, no, Leetch was never going to be confused with Scott Stevens (nor Lidstrom for that matter) defensively. But he never a slouch either, by no means, in his own end.
And he is headed to the Hall of Fame, without a doubt, upon his retirement.