This law makes a lot of sense to me, but be prepared for FR's own left lane vigilantes to start spamming the thread with, "If I'm going the speed limit, I should be able to drive in whatever lane I want to! Why should I let other people break the law?"
That's one of the problems here in FL. Some older people feel morally obligated to go the speed limit in the left lane and block people from passing. What you say is their logic. If you are going the speed limit, you can't pass. Since it's against the law to speed, you should not be trying to pass. The law has been on the books for years. It's called obstructing traffic, even if you are doing the speed limit. I know becasue an older acquantance did get a ticket about 8 yeras ago for doing that on I-4. The state trooper was not amused.