On a quick glance the tutorial seems to overcomplicate it a bit.
Whatever package you use, doing a split screen requires four actions as I see it.
1. Select the part of the video you wish to appear in the left half of the final screen (crop)
2. Select the part of the image you wish to appear on the right half
3. Position the left half
4. Position the right half
Put your clips one above each other on the timeline.
In Vegas 1 & 2 are achieved with event pan & crop
(select the event pan & crop, release the "maintain aspect ratio" button, move the left or right sides inwards to resize the image, drag the "F" frame left of right to get the correct part of the image in your new, narrower frame)

Parts 3&4 are achieved with track motion
Select the track with the image you want to appear on the left, click the track motion icon (on the track header) and drag the frame so the image moves to the left. Repeat on the other track for the right half.

There are much fancier ways of doing this with parent/child relationship & masks which is great if you have loads of different clips, but the above is simple and quick (as with everything, familiarity with the product makes it a much simpler task)

Hope this helps

__________________
Tim