If it sounds too good to be true - it probably is!
I think you are fooling yourself on two different levels here. For one thing you are only looking at one, 24 hr., cycle which is "8 on - 8 off - 8 on". The next 24 hr. cycle would have to be"8 off - 8 on - 8 off", and then "Flip-Flop" every other cycle. Otherwise you are just looking at a "regular" cycle of "16 on and 8 off", which would indeed keep them in perpetual veg.
On the other hand, the plant requires 12 hours of "uninterupted darkness" to accumulate it's full dose of "Sleepy-time" hormones that allow it flower - "Yo, you got's to let the bitch sleep!". Although there is some evidence that once a plant has a well established flowering stage, that it will maintain flowering with a reduced amount of dark hours (perhaps "10 off - 14 on").
Whenever you reduce the "Circadian Cycle" to less then 24 hours, you force the plant to spend an inordinent amount of time "Waking up" and "Going to sleep". These "Turnover cycles" just eat up energy and waste time. Following this idea to the other extreem, it makes sense to run your lights "14 on and 14 off", just an idea!