sorry, I don't recall the point. The key word in your paraphrase of what you think I said is, "if... that was the case", then it would have been debatable. In short, the WCF says nothing to support presumptive regeneration nor condemn it. The Continental Reformed churches most assuredly believed it and taught it. In the First Head of Doctrine, Article 17 they wrote:
Since we are to judge of the will of God from His Word which testifies that the children of believers are holy, not by nature, but in virtue of the covenant of grace, in which they, together with the parents, are comprehended, godly parents have no reason to doubt of the election and salvation of their children whom it pleaseth God to call out of this life in their infancy.
Further, the official "Form for the Baptism of Infants" clearly states that the children of believing parents have had their sins forgiven due to the blood of Christ... etc. which you can read from the attached file. But this view was not typical of paedobaptists although it has grown in popularity in recent years. What you read in the WCF was the majority view of the 'Westminster Divines' and which was believed by the vast majority of the membership of their respective denominations/churches.