When there are cards on all 18 holes for tournaments, the pace of play can only be as fast as the slowest card on the course. When cards are arranged in the 2nd round by scores, this becomes even more of an issue.
I've observed good rated players shooting quite low scores holding up tournament progress. It's not about that 30 second "shot routine." What's slowing the card down is the stuff they're doing the other 15+ minutes per hole.
So I don't think it's fair to say the players making the most throws throughout a round are typically the slowest on the course. Sure more throws inherently takes a bit longer. But some extra shots isn't an issue if the group is conscious of their position relative to the group in front of them. The problem is all the diddling around in between shots, not being ready when it's a players turn, dawdling about between holes and taking more than a moment to get scores down and get right up on the next tee, that eventually leads to a cards slow play and falling behind.
Additionally, the clause in the excessive time rule I posted previously is the "reasonable amount of time to arrive at the disc" is totally subjective and thus basically non-enforceable. So you have to rely on the Speed of Play rule in Code of Conduct as what is "falling behind" is less subjective. However, that rule can only be called by a tournament official, which there may be only one at the event. As such, the TD is unable to effectively marshal the entire course for speed of play.