I should clarify I don't necessarily endorse the approach! One point I have seen made (and this may only be semantics) is that "fair contest" does not necessarily mean an "equal contest", and that in this context a "fair contest" should reflect the fact that the non-putting in side is the one which has committed the error etc. - i.e. it is "fair" that they should be materially disadvantaged in the contest. Now, of course, there are already a number of ways in which the non-putting in side are already disadvantaged, but one way in which they are ADvantaged is that all 8 of them can push, whereas one of the putting in side is now obligated to strike, thus decreasing his ability to push. This arguably results in a contest which goes to far towards equality (given that the error was by the non-putting in side) and so to restore the appropriate "fairness" of the contest (i.e. a contest weighted in favour of the putting in side) it was necessary to make the adjustment regarding alignment.
You will have guessed from the above that I am a lawyer and used to putting forward arguments for a case I don't necessarily endorse!