I'd like to understand the logic behind how Movie Maker implements scene transition animations.

Consider the following:

I have a movie that consists of two scenes, each scene is 10 seconds in length. That means the total movie time is 20 seconds.

If I then add a 1.5 second transition animation (bow tie if anyone wants to play along at home) to scene 2 Movie Maker then does the following: The first scene is shortened to 8.5 seconds (even though in the edit window it still says it is 10 seconds in length) The second scene is 10 seconds in length, and the total movie length is now 18.5 seconds.

Although I did not intend to change the total length of the movie by adding a transition, I can understand what movie maker is trying to do and I can understand the math it is using.

So lets double the length of the transition to 3 seconds. The first scene is shortened to 7 seconds, the second scene is 10 seconds and the total movie length is now 17 seconds.

And now, if we double the transition length again to 6 seconds the craziness begins. The first scene now becomes 6.7 seconds in length, the second scene remains 10 seconds and the whole movie is 16.7 seconds.

My guess is that the transition animation that I chose (and all the animations) can't last more than 3.3 seconds even though Movie Maker lets you override the default setting to a maximum of 10 seconds.

Are there transitions that last longer than others? Is there any transition that can last 10 seconds?

And in case there is ongoing development on a new version, could someone stop Movie maker from changing the length of a movie when a transition animation is chosen? It really makes things messy when you're trying to do editing and timing things to a music or narrative track.  If its not possible to do this, then somehow indicate what the maximum length of a transition is and don't let the users override it.