Good to see you posting again young Browners.
Woe is me, I don't know what the Tina Turner video you refer to looks like. But hey, to split screen on Mediastudio try this,
1. Place your first clip on track V1 and set a moving path where the width X is set to 5 for both keyframes.
2. Place your second clip on V2 and set a moving path where the width X is set to 715 for both key frames.
This overlaps both clips by 5 pixels in the middle of the screen.
Its the blending bit that is puzzling me because I don't know the video you refer to. But you could try a simple transparency overlay by setting the transparency for both clips to say 5% or 10%. Or you could try a motion blur, a blur or smart blur video filter to both clips. Alternatively you could create the movie at this stage and then blend using Video Paint.
If you can post a screen shot of the specific blend effect that you want, then I will try and post back more specific instructions.
Meantime good luck.
COMPAQ something or other with 500Gb Boot Disk, 1Tb external Firewire Disk, 4Gb Memory and a super duper sound card, 19" TFT Monitor etc etc etc
Sony TRV33e : Sony TRV310e : Canon XM2
Sony Vegas Studio editions to v11
Remember, there is always more to learn than there is to teach.