A mismatch in the offical development documentation

This is the description of the Track.Fog command in the offical documentation:






However I found this description of the command Options.FogBehavior in the same document, prior to it:

So I got confused.
Track.Fog seems can not only be used at the beginning of a block if the Options.FogBehavior is set to 1.
But there is a warning post placed right there says it can only be used at the beginning of a block.
So, CAN Track.Fog be used in somewhere else than the beginning of a block?

Take this example:

Code:

0, .fog 0;200;150;150;150
100, .fog 0;200;0;0;0
200, .fog 0;200;150;150;150

Options.FogBehaviour controls the interpolation mode.
When this is set to 0, our initial fog reaches full intensity at 25m. At 100m, it then interpolates over the next 25m (block) to reach the value set there.
When this is set to 1, our fog starts at full intensity at 0m, and over the next 100m it blends to reach the value set at 100m


In either case, it can only be used at the beginning of the block. I haven't investigated specifically why for this post, but that was always the limitation with BVE2 / BVE4.