However the bottom line with AD&D has always been that the 'rules' are guidelines, it's up to each DM, and her/his group of players how they interpret those rules, or even if they use them at all. In terms of the game, Bioware/Black Isle is the DM, they laid down their 'house rules' so my view is as a basic tennet we should abide by them.
There is however a subscript to the bottom line, and that is you bought the game, in the end it's up to you how you play it, neither you or anyone else has to pay the least attention to moans by old fuddy duddies like me!