Theoretically I'm in favour of motion sensitive lights. Very good energy savers. But, now that I work in an office building that has them, I realise that they are work control devices. You're just settling down on the bog for a good read and the light goes out. You wave your hands around, but you can't turn it on again from inside the cubicle.... You have to go back to the office.
Gives a whole new meaning to the phrase "motion sensitive".