Topping is an excellent way to control height. As this is usually not a problem for me, I generally do not top my plants. IMO, although topping produces more colas, I think that the plant slows down its growth rate a little in reaction to trauma? It seems that the untopped plants, in a side by side comparison do not appear to slow down and therefore produce slightly fatter buds overall.(if harvested at the same time)
This has been my observation over the years, but I've never kept records or weighed anything to make certain....just a hunch!