If it's statically spliced, yes. but if it is dynamically spliced in, it'd be harder to do the same to block it. You'd have to detect the ad itself, and YouTube

If it's statically spliced, yes. but if it is dynamically spliced in, it'd be harder to do the same to block it. You'd have to detect the ad itself, and YouTube may not allow the video to be timeseeked, which might make the viewing experience suck with a black screen for the duration the ad.