Exactly right. Everyone has their own method/style, and stop and go traffic will wear your leg out, regardless of how relaxed you are. I can still remember my tension and anxiety when I was the first car at the stoplight. I hated being honked at, so I was really nervous about getting started in a timely and smooth manner. It is really embarrassing to stall with folks waiting behind you. Just keep practicing and you will get comfortable and proficient.