with a 1000w hps (which i use) i tend to trigger at at least 45cm, depending on the strain. if the strain has a lot of indica i may let them get to 45cm or more as they dont grow as much as sativa when you trigger them.
some strains will produce almost everything on the top bud. those are the ones best triggered small and in high numbers.
if the side branches produce a lot of bud, grow it taller (without letting it stretch) and bend the stalk, branches etc as it grows ie bend the top down and tie it so another branch becomes the top, and repeat as many times as you can. that way you have many top buds. this way is more suitable to sativa strains
though every strain acts differently.
if i trigger a 45cm PurePowerPlant i would expect at least 3.5oz dried buds under 1000w hps
something with a lot of say Tai in it id expect slightly less at first but id harvest the top buds and the lower buds would continue to swell and after another week or two you have the same amount as the first harvest. i think this is a characteristic of "jungle" strains where seasons are less importaint.
to sum up, it depends on the strain. some (armageddon skunk,eg) seem to produce better using the sea of green method. others (haze, eg) as larger plants. as you know you get to know the strain and whats best for each type
some strains it makes little difference what you do and it comes down to how much space you have