I have such a hard time buying any argument against toll lanes.
Let's say you go to a fast food restaurant and want a hamburger. The hamburger costs $2.50, just for the sake of argument. The clerk asks you if you want fries with that. Fries cost $0.75, again, just for the sake of argument. Maybe the fries are worth the extra 75 cents to you, maybe they aren't. The US 69 proposal is like the hamburger and fries. If you use US 69, you're already committed to the hamburger. You've invested the money into a car and fuel, the $2.50 example. The existence of the toll lanes give you the option of adding fries to your order, for a bit of an extra cost. Either it's worth it to you, or it's not. What about the normal lanes on US 69 (the hamburger) getting more congested? Well, sometimes fast food restaurants have long lines, too, right?
Here's another example. Let's say you order a package. I don't care what it is. But normal shipping costs $5.00, and it gets to you between one and two weeks from the time you order it, or maybe longer if it's a busy season like the holidays. For an additional two bucks, you can get express shipping that guarantees you'll get it within five business days. The toll lanes are like the express shipping. Either it's worth it to you, or it's not.
Now, to the other side of the coin, let's suppose we add lanes without any additional cost to the end user. That's like selling the burger and fries for the original $2.50 price of the burger. That's like selling the express shipping for the original $5.00 price of standard shipping. Maybe it works as a short-time promotion. But is it really a sustainable business model?