According to this FAQ you can switch weapons between iteratives when not using TWF. Does this apply generally?
That is, can a character with improved two weapon fighting switch which weapon is considered primary between his first pair of attacks and his iterative? (eg. to better get around DR that he only became aware of after the first attacks) If he has more iteratives than he has TWF feats for can he switch which weapon is used for which iterative in accordance with the above FAQ? (eg. because he is in position to attack two enemies with different kinds of DR and one drops while he has iteratives remaining)
In a related case, does initiating TWF with a double weapon (or unarmed strike and a one handed weapon that can be regripped as two handed) prevent the weapon from being used two handed if the character has excess iteratives? (eg. if a character only the first TWF feat but at least 6 BAB can he make two attacks with a quarterstaff as a double weapon using TWF at 1x a 1/2x strength but still make his unpaired iterative as a two handed attack at 3/2x strength)