good discussion and posts guys 
some good points raised that i wanted to comment on.
Plant Numbers Dictate yields - i agree that this is largely BS and, given that in most places where growing is illegal, certainly UK, that PLANT NUMBERS DICTATE PRISON SENTENCES - i think thats its an irresponsible thing to bandy about. sure in some systems your plant numbers will influence your yields, as will a whole raft of other things. ive debated this with DHF, who im sure killed it with his vertical systems, and eventually he acknowledged that it is not the whole story. There are many ways to get high yields, not just one, and not all of them involve high plant counts.
its always a mistake to presume that just because something worked really well for you - that it will also work just as well for everyone else and that it is the ONLY way to do it.
Veg time - i agree that it should be taken into account in any accurate calculations... but lets face it you can veg plants just fine under very low wattages of light... at the same time the power consumed in rooting large numbers of cuts should be taken into account, and changing the name of vegging to 'pre-vegging' means very little, it still uses power that should be taken into account.
i can veg my plants under 5-10% of the lighting wattage that i flower them under, and i veg for 2-4 weeks, most of that in my mum cab where the tubes would be on anyway (i keep my half a dozen or so mums and vegging plants under 42watts of T5, the last two weeks of veg i get my 4 plants under 44W of LED. and i can root 8 cuts under a 9w cfl, no bubbler or any other power used.
size of grow in relation to gpw yield - i agree that small grows seem to get better efficiency, but the only reason for this can be that small grows are more efficiently managed with greater attention to detail. lets face it a 1000 gives out about 10% more light than 4 x 250.
what it comes down to is making sure that whatever way you choose - do it well and you will get good yields.
VG
some good points raised that i wanted to comment on.
Plant Numbers Dictate yields - i agree that this is largely BS and, given that in most places where growing is illegal, certainly UK, that PLANT NUMBERS DICTATE PRISON SENTENCES - i think thats its an irresponsible thing to bandy about. sure in some systems your plant numbers will influence your yields, as will a whole raft of other things. ive debated this with DHF, who im sure killed it with his vertical systems, and eventually he acknowledged that it is not the whole story. There are many ways to get high yields, not just one, and not all of them involve high plant counts.
its always a mistake to presume that just because something worked really well for you - that it will also work just as well for everyone else and that it is the ONLY way to do it.
Veg time - i agree that it should be taken into account in any accurate calculations... but lets face it you can veg plants just fine under very low wattages of light... at the same time the power consumed in rooting large numbers of cuts should be taken into account, and changing the name of vegging to 'pre-vegging' means very little, it still uses power that should be taken into account.
i can veg my plants under 5-10% of the lighting wattage that i flower them under, and i veg for 2-4 weeks, most of that in my mum cab where the tubes would be on anyway (i keep my half a dozen or so mums and vegging plants under 42watts of T5, the last two weeks of veg i get my 4 plants under 44W of LED. and i can root 8 cuts under a 9w cfl, no bubbler or any other power used.
size of grow in relation to gpw yield - i agree that small grows seem to get better efficiency, but the only reason for this can be that small grows are more efficiently managed with greater attention to detail. lets face it a 1000 gives out about 10% more light than 4 x 250.
what it comes down to is making sure that whatever way you choose - do it well and you will get good yields.
VG
) heres is 1816 gram wet plant gave me a pound dry do you see any difference ??? the screen is one plant trimmed 
gone from giving info to the usuall clashes! 
