The ones that say, e.g. that if you have 10 men educated in software engineering per one woman and you change your hiring practices to be less discriminating, you shouldn't suddenly expect to have 50/50 gender balance among tech workers in your company. You should see that 10/1 proportion reflected in your staff, if you hire based on merit alone.

I don't think so, because the rates are not immutable, and you're discounting causation going the other way. If the women who are hired are treated well (which would require their employers to undergo some training), the rate of women attaining software education is likely to rise. "Downstream" likely has a strong effect on "upstream".

I agree, but the issue is with a post where someone apparently claims to be getting such results right now.

First, I don't think they claim a 50/50 split. I guess there's still room for improvement even before hitting the applicant pool limitation (I have seen it, too, BTW, when we hired; the number of women applying is higher than their representation in startups).

Second, it's also very possible that there is a local, fast, feedback loop. I think women would be more attracted to companies that already employ a higher number of women, and are known for a hospitable working environment, so it's likely those companies will receive a higher share of women applicants.

I don't think so. If they are treated well they won't complain and you will never hear about them.