Misconception: Two female witnesses are equivalent to one male witness

Background: Some think that a male witness is equivalent to two female witnesses in all cases, due to misusing one verse and applying it to all situations, irrespective of context.

This is only true for financial/business transactions:

O you who believe, if you borrow debt for a specified period, then you shall record it. Let a scribe of justice record it for you. No scribe should refuse to record as God has taught him. Let him record and let the person who is borrowing dictate to him, and let him be conscientious of God, and let him not reduce from it anything. If the borrower is mentally incapable, weak or cannot dictate himself, then let his guardian dictate with justice. And bring two witnesses from amongst your men, if they are not two men, then a man and two women from whom you agree of the witnesses, so that if one of them errs/forgets, then one can remind the other*. The witnesses should not decline if they are called, and you should not fail to record it no matter how small or large including the time of repayment. That is more just with God and better for the testimony, and better that you do not have doubts; except if it is a trade to be done on the spot between you, then there is no blame on you if you do not record it. Have witnesses/evidence if you trade. No scribe shall be harmed nor any witness; for if you do so then it is vileness on your part. Be conscientious of God so that God teaches you; and God is aware of all things. [2:282]
*note that it says if one errs/forgets then one can remind the other, implying both women may not be needed to testify if one can remember without problems. Secondly, there may be no need for witnesses to testify at all if the written agreement is not disputed by either party.

The Quran implies that the man has a wider duty of care than the woman, regarding maintenance of the family/household [2:228, 2:233, 4:34, 65:6], and since women are biologically endowed with certain qualities such as pregnancy and breastfeeding this naturally makes them more likely to raise children, so generally speaking men are likely to have more experience in financial transactions. Another reason for this one-man and two-woman witness arrangement could be the protection of women from being subjected to high pressure by the party breaching the contract, which is mentioned at the end of the above verse. The presence and support of other women might reduce the pressure and possibility of perjury.
This case is also unique in the sense that it requires witnesses to be chosen, which is different to being an accidental witness to a crime for example.
Elsewhere in Quran it states the underlying principle of transactions/trade and that is it must be mutually agreed upon [4:29], which would also mean the witnesses would have to be agreed upon, as implied in 2:282. Thus, it could be argued that this core principle could be applied in a situation when no men were available and only women witnesses were available, as long as the transacting parties agreed. This hypothetical is not explicitly discussed however.

For other situations, such as a sole accusation by the husband against his wife of infidelity a female's testimony is equal to and effectively cancels out a male's testimony [24:6-9].

Likewise, in other examples in which witnesses are required, no differentiation is made between males and females [4:15, 5:106, 65:2].

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