This gets kind of philosophical, but the problem is two conflicting technical interpretations of nothing. Nothing can either mean content that is fully transparent, or it can mean having no content at all.
1) When a layer has nothing / no content in it, it doesn't have to render and can be skipped.
2) When a layer is multiplied with nothing / fully transparent, the result should be nothing / transparent
I think we can all agree that both statement 1 and 2 are valid assumptions and technically correct.
The problem starts when you combine them.
When you eject a layer in multiply mode with a transition, you transition to statement 2. The image will slowly become fully transparent, because you are in transition to nothing / fully transparent. The layers underneath will eventually be completely hidden, because something multiplied with nothing results in nothing.
But. But. Buuuuut. When the transition is over, the outgoing clip is ejected and you enter statement 1, where a layer can be skipped because it has nothing in it. This means the multiply blend is completely skipped and the result is a jump to the layers beneath being completely visible, because they are no longer being multiplied.
So, there we have it. Two things that are technically correct, yet the result is not usable. What a pickle.