drawing stickfigures is pretty damn easy my good sir, and it looks joined because he used the line tool, not the brush tool
the easy way to tell if something is made on flash, is to right click on the movie, and if a window comes up with
zoom in zoom out show all quality > play loop rewind forward back print settings ABOUT FLASH PLAYER "insert number here"
it was made on flash.
also, pivot is not the only tool in the worl that has joints my good sir, as i have been aniamting for 8 years with flash, i find it pretty damn easy to tell a flash aniamtion, from another animation created on another programme.