We all owe Gary XP for this carry-on. 
I'm pretty sure this is a style debate, and the sides correspond roughly to New School and Old School.
So, if Hickman had just given the players cool powers and advised the ref with something like, "you should be guided by the dice, not mastered by them - if it comes down to throwing out a bizarre dice roll, or the same plot, the die has to go!", rather than Answers To Their Tactical Problems - Dragonlance wouldn't be a railroad? What would you call it - a railshooter?
This is something of a distraction, anyway. The OP's question is about how to deal with a ref who's being a bit tight on downtime - I'm reluctant to call that railroading at all. The debate that's since developed from Starfox's thought experiment is more about scripting than railroading. I can railroad you into a non-scripted event. For example:
One point to note, however, is that when I hit the characters with penalties for not taking better shelter during the storm, I am merely interpreting the rules to them. The weather wasn't my decision (it surprised me, too). According to the setting notes I'd prepared independently of the weather, there was a possibility for shelter - it could just as easily have been a burned-out watchtower, a traveler's shrine, the base camp of a band of robbers, or nothing at all.
By scripting the exact same session, I own it. If the characters take penalties for not doing what I expect them to do (go to the witch's cottage for the scene I wanted to run), I am punishing them for not following my script.

I'm pretty sure this is a style debate, and the sides correspond roughly to New School and Old School.
This. THIS IS RAILROAD!Dragonlance is a Railroad because as you point out it does not support player freedom in any significant dimension, the players are essentially just along for the ride. Where there is significant player freedom in any of the dimensions you have identified, it is not a railroad.
So, if Hickman had just given the players cool powers and advised the ref with something like, "you should be guided by the dice, not mastered by them - if it comes down to throwing out a bizarre dice roll, or the same plot, the die has to go!", rather than Answers To Their Tactical Problems - Dragonlance wouldn't be a railroad? What would you call it - a railshooter?

This is something of a distraction, anyway. The OP's question is about how to deal with a ref who's being a bit tight on downtime - I'm reluctant to call that railroading at all. The debate that's since developed from Starfox's thought experiment is more about scripting than railroading. I can railroad you into a non-scripted event. For example:
It's 8pm, and we're on to day 3 of a wilderness expedition. I roll on a weather table for the day, get a freak roll, it's a storm! Glancing at the notes for the hex the party happens to be in, I see that a witch's cottage is there. I figure that the storm can set in midday and the players can take shelter in the cottage. But oh no, you miserable miscreants want to create a makeshift camp where you are, and build a fire! Well, too bad! The high winds prevent you from getting it started. You can smell woodsmoke coming from upwind. What's that? You try to create a windbreak? Uh... it catches fire, then the winds put out your campfire before it really gets started! There's a smell of delicious food accompanying the woodsmoke!
WARNING: this is ham-fisted and not something I'd recommend. If I'm really keen on the witch's cottage as a scene, I should have the party pass it by before the rail really starts to come down, but accept their decision if they decide not to backtrack. (They're not necessarily being silly: traveling during a storm can be very dangerous, and a makeshift shelter is better than none at all.) When they're setting up the fire, all that needs to be said is, "Yeah, you get your fire started and huddle in. It's a cold and uncomfortable way to spend the afternoon. The weather still hasn't let up as dusk approaches - it's going to be an unpleasant night." Short of any more player action, they'll just wear some minor penalty from fatigue the next day.
One point to note, however, is that when I hit the characters with penalties for not taking better shelter during the storm, I am merely interpreting the rules to them. The weather wasn't my decision (it surprised me, too). According to the setting notes I'd prepared independently of the weather, there was a possibility for shelter - it could just as easily have been a burned-out watchtower, a traveler's shrine, the base camp of a band of robbers, or nothing at all.
By scripting the exact same session, I own it. If the characters take penalties for not doing what I expect them to do (go to the witch's cottage for the scene I wanted to run), I am punishing them for not following my script.