I think when people put a phal closer to a window and it blooms, the immediate thought is that it obviously needed more light. But unless you have amazing ventilation, the temperature of the air behind the glass of a sunny/bright window in your house is always going to be higher than the interior of the room the plant is in. It's also going to lose heat quicker than the interior of the room as temperatures drop outside, and will likely also be a little bit colder than the interior of the room during the night. Of course, this does depend on where the heaters/radiators are in your home, if you have double-glazing, etc., but I think overall, depending on how close to the window you've moved your phal, you're not only giving it more light, you're introducing a different temperature range, and it is probably the difference in max/min temps more than anything else that finally encourages the plant to bloom.
Anyway, that's just my