Transparency in Edit Mode

Dear Blender Artists,

is it possible to see the tranparency automation without rendering?
I set two keyframes for z transparency and would like to fade out the upper (blue) letters a,b,c,d which are connected via an Empty. I want to make fades and croossfade transitions of text blocks as you see in the attachment below.

in the attachment you see the green box, having an alpha value on the right keyframe . The left keyframe
is at 1.000.

but: If I play that sequence (ALT + A), that value does not change over time and stays at 1.0000
in the object window.

After rendering on the other side everything looks good (the transparency occurs as it should), but certainly takes some time for rendering.
Regarding the idea of making a bunch of 5 minute movies…

I would like to see the result in between while working on the show.

So what would be the best ways to let cross dissolve transitions show during the working process without having to render the whole thing. (If possible at least, sure…)
Another idea could be using cross fade transitions of different layers. (if possible)

Thanks for your experience and advice!