I can understand the concept of a segmented or articulated fly, and the method described seems to show that, when you set aside all the dressing materials save the 2 x 1" plastic tubes, and the connecting 2" rabbit strip, you will end up with a construction which is 2 x 1", plus 2" rabbit strip, minus length of rabbit strip used at each end to tie onto the adjacent tube segments, ie total length is just a shade shorter than 4".
However, add the tail materials for the rear tube section, and the profile will significantly exceed the 4" - ie from head to tail tip.
I can see that the rabbit strip connecting the 2 tube segments together will, when under tension, will keep the fly construct at its full length.
However, what I have a problem in understanding is how you keep the two tubes from collapsing together - towards each other - when fishing on the swing. The tubes are slid onto the leader, and you form your non-slip loop, attach the 'stinger' hook to the loop, and off you go. But in the water, the non-rigid rabbit strip doesn't hold the tubes apart, it just prevents them from getting further apart when tensioned or stretched. The leader passing through both tubes and onward to the non-slip loop & then the hook will be, say 10 to 15lb maxima, which is not rigid either. I see nothing else between the 2 tube segments which holds the segments apart.
In the water, holding the fly line, & via the tip, through to the leader, the top section of tube will be pushed downstream, relative to the rear tube section, and the length of the fly construction will collapse in length.
Am I missing something???