So, I messed about again (I really dont do much else...)
and... I am not sure if this is a bug, a feature, or both.
If you place Diesel into an environment saturated with Hydrogen under high (50+) pressure, some of the Diesel combusts due to pressure. The rest of the Diesel forms oil and water.
Now, I am aware that carbohydrates, when burning, release watervapor as one of their products, so maybe this is intentional? Whichever the case, if someone like jacob1 could tell me if I found another bug I would be very happy. (And people, please dont be angry with me if this is common knowledge.)
I see. I guess they also didnt consider that hydrogen doesnt burn above 50 pressure, making this remarkably nonflammable