It doesn't look like there's that much difference in the graph. Perhaps a little. It does look like the slide on the 'L' is moving slower than the Shorty? How about the claim it feels or compares to a short barrel 22LR?
I estimate about 10 degrees less flip with the L vs. the S. Visible on high speed video analysis, but hard to see with the naked eye. I watched someone else shoot both the long and short yesterday and I couldn't see the difference. He watched me shoot both and couldn't see the difference in flip.
You can feel the difference when you shoot both. The other guy that tried both had never seen a Boberg before yesterday afternoon. His comment after shooting both was that the L came back on target faster than the S. His normal carry is a Glock 19. Heading back out to the range this afternoon to let a few more people try the L and get their thoughts on the difference in flip and felt recoil.
I really wanted to find a Bersa Thunder 22 to compare with the L, but the one store I visited only stocks the Thunder 380's. Arne's 22 comparison was based on a pistol similar to the Bersa Thunder 22. I've never shot a blowback 3.5" 22 pistol so I can't validate the comparison.