Actually you can push yourself:
example on FUMBBL
Such selfpush will end at least to the square that the original blockee occupied, as that square is vacated the time the blocker is pushed there - no chainpush should occur after that, chainpush comes to rest.
If you add the players from the cards and start the pushing from an appropriate place outside of the accelerator circle, it is however possible to have more players in the chainpush than there are squares in the chainpush. This will cause as many pushes as the blocking coach wants. This may move some players more than one square from their starting position with the one block.
With sufficient number of players it is also possible to chainpush itself a couple of squares.
I leave the construction of these two situations as an exercise to the reader as I don't currently remember where those things were posted before.