What does speedrun mode do?

A new speedrun mode (--gotta-gomez-fast) was the most publicized new feature of the 1.12 patch, but I can't find any details about it online. How does it work?

Solution 1:

It adds a fourth option to the three save slots (called "Speedrun"). It's a separate mode from the main game that adds a stopwatch timer in the top right corner and adds splits (timestamps) for each cube. There is no "saving" in this mode, but a "Reset run" option is added to the game's menu. Here's a video of the mode in action.

The feature doesn't appear to speed up any of the game's transitions or loading screens, but it was written to not count loading times that differ between systems. (The feature request mentions requiring singlethreading but that doesn't appear to have made it to the final.) PC installations should dump the run's split times into C:\Users\<USERNAME>\AppData\Roaming\FEZ

To enter speedrun mode, use the --gotta-gomez-fast flag on startup. On Steam, right-click the game's entry and open its properties to "Set launch options":