So, in conclusion, just grow the damn plants and keep your mouth shut about it, grow only for yourself and a couple close friend and you'll have no problems. Common Sense is key here, if you have a greenhouse full of pot plants and lights for them... you might get caught. Your closet? Not to likely, because in the United States and Canada(*) a warrant is required to search a house.
* = If you are Canadian and have a firearms licence, you could be subject to safety inspections but generally you receive 24hrs of notice and they are only allowed to look in areas that are for firearms storage.