Long commute, near-misses: online vs in-person defensive driving courses

[Joshua_T]

I recently started a new job that requires a long daily commute on a busy interstate, and after witnessing a few near-misses, I've realized my driving habits have become complacent. I want to proactively improve my skills and awareness, so I'm looking into taking a defensive driving course, but I'm unsure if the standard online version offered for insurance discounts would be as valuable as an in-person, hands-on program. For those who have taken advanced driving courses, what specific techniques or mental frameworks did you learn that most changed your everyday driving? How do you consistently practice scanning for hazards and maintaining a safe following distance in heavy, fast-moving traffic, and are there any recommended resources or drills for sharpening reaction times and learning proper evasive maneuvers in a controlled environment?