i know this is like a year old, but why does everything think topping a plant gives you more tops? the reason for topping is for height control, space control and to specify the amount of tops you want to maximize potency for your space, its not to give you more tops. if you truly wanted a ton of tops, you would not top your plants at all.
for instance a plant that has never been topped will grow so many tops you wont be able to see in your room let alone the inside of the plant, that is why a lot of indoor growers who cannot afford a room full of 1000w bulbs, top their plants to accommodate their space and to maximize potency per watt. if you have lower wattage lights you dont want your plants to grow normally without being topped because you will end up with so many tops that are just too much for the amount of light you are using, which in turn gives you a low potency plant that will yield a lot but wont be worth much and most likely wont be dense either because of so much energy being needed that a indoor grower cant provide unless using several 1000w HPS.
i just had to state the purpose of topping is not for more tops, but for control over the plant to get the most out of it considering the space its in. topping is used to determine the amount of tops you want to grow and think will work within your space and for your lighting, lower lighting and less space, you want to top your plants to only have 4-6 tops at maximum or if you have all the space you need and high wattage bulbs there is no need to top at all.
that is why you will never see a lab facility with topped plants, or even serious growers who can grow in factory type facilities with topped plants because they would only be hindering their yield, they have the lights and the space to provide all those tops with the energy and space they would need to grow properly, versus most indoor growers using lower wattage lamps and way smaller spaces.
more simple explanation, you top your plants for less tops. if you wanted all the tops you can handle, dont top your plants at all and see how ridiculous they grow. ive had un-topped plants grow more than 12 tops easily, yes i yielding a crap load but the potency wasnt there because i couldnt supply it with enough energy, hence why topping is around.. to maximize quality given the space and lighting.