I am not sure whether there is any unequivocal evidence that supports the government view that maximising attendance maximises progress. It seems obvious, but there are other issues influencing outcomes.
It's neither obvious nor, I doubt, true. The research the government carried out shows nothing about increasing attendance, and whether or not this is correlated as causal. In fact, I doubt it is causal.
Second, "progress" if narrowly defined as doing well on SATs, is actually not a great measure. I couldn't care less if my DCs did well on the SATs. It does them no good.
I'm not sure its any weaker than any of the other "evidence" used to support policy - you cam always find research that supports a particular case!
it's weak because all it does is show a strong correlation.
What I do disagree with is parents making decisions knowing full well that the outcome could be a fine, and then bleating that it's not fair when it happens to them.
It can be all of legal, predictable and unfair. There is no contradiction there.