I think i agree with Trun : if not a bug it at least doesn't feel right, if you acceleration is supposed to be fast you should accelerate in the opposite direction at the same rate wether you're moving or not.
This is how it would be if you coded the first panel in the most straightforward way possible, so yeah it feels like a bug and i feel like the turn speed thing is not very clear about how it does what it does at least for me
That being said the essay is still fun but that feels like an oversight