You found a very good, although now slightly dated resource. BTW, Object based automation is now called Region based automation (Logic switched from the term object to region). Step 10.6 is one way to do this, but I think I'd only use this for copying multiple parameters simultaneously. To add to this, if you have the automation event list open, you can open an instance of the Arrange window and it will just show track automation as regions you can move, cut copy, paste, etc.
If you are just wanting to copy a single item of TBA (track based automation) then just select the parameter you want to copy. We'll use volume. Then select the area of automation you want to copy. For the entire track, either command-click on the automation fader or option click on the first node. For a specific area, shift-click and drag to create your selection, or option-click from the point where you want to select nodes to the right.
Then use standard copy and paste commands - copy from target track, select and paste in destination track. Your destination track will now have the volume automation envelope.