Your first argument is satisfied by 2 and 3 of the post you replied to.
Your second argument boils down to, 'perhaps they have a larger female applicant pool than you suspect.' However, it doesn't really seem support an argument that the company will look different than the applicant pool.
Well, I'm assuming "applicant pool" means the pool of all people applying. My point was that even if women are a small portion of the applicant pool, they may represent a larger quality-weighted portion of the total applicant pool. I agree that if as your population becomes large, you should asymptotically be approaching the demographics of your quality-weighted applicant pool.
Note: By "quality-weighted" I really mean something more complicated like "ROI-weighted", since it could also be that because of your reputation as a "female-friendly" employer, high-quality female employees will be willing to work at a lower salary than they would otherwise demand at a "male-dominated" workplace (e.g. "Well, company X pays better, but I really like the culture/people/policies at company Y...")
Your second argument boils down to, 'perhaps they have a larger female applicant pool than you suspect.' However, it doesn't really seem support an argument that the company will look different than the applicant pool.