Cool!
Jrosek's cut looks like it has more indica in it than what you run.... but in any case there is more benefit to growing bud than fan leaves as long as the plant has the structure you like. At 2 weeks and then at 6 weeks works for fan leaf removal. Lollypopping or pistilwhipping is fine... think the intention was more for SOGs with 3 - 4 ft. plants in them b/c even with 400W, the penetration is enough to fire up lower bud sites. If they are removed yield takes a hit unless the grower is inexperienced.
In your case you will like the results. You can always let it go more than 2 weeks then start thinning at 4 wks. I just cleared out the top fan leaves in my experimental 400W cabinet but that was at 2.5 wks, only on some plants and was done so they don't hit the light. I am presently whacking most all fan leaves in another system (vertical) right now. Lots of theory and diff opinions and best way is to just try it.
Your plants are shorter and would benefit by NOT lollypopping, in my opinion, as long as you manage bud sites and open them up. suckers can still go but wait till your sure stretch is done or it will turbo charge the stretch. Basic pruning, take of side branches increases height and you don't want that. Please keep using a horizontal orientated light. You talked about an umbrella-style and I hope yer not going to a vertical bulb in one of those growstars or supernova. If I could get you to try an Adjust-a-wing... oh man you'd like it.
If you rock a MH bulb until 3 or 4 weeks into flower, you will increase your yield in my opinion. (don't forget to then switch to HPS). The plant will stack nodes, stretch will be down and the blue light will also result in a more robust root system. If you have circulation fans blowing well, expect a thicker stalk. If you have the ability to precision control your temps/humidity, drop temps on the flip till the stretch ends. As calyxs start to stack, get it hotter then.
Anyways, thank you for the reference to icmg thread. Something to read all night !! I'll be changing/new account my handle to match my icmag and cannabis-world handle so i'll post that in all of my current 4 posts. The info i wrote to you is from my direct experience and has been tested and proved in my space with the strains I work with. Most important is the bulb... don't think the lumens are more important than spectrum at the flip and thru stretch. If you can afford it, try the MH and don't switch it out till almost 4 weeks. Trust me. For people who can't afford both bulbs and read Jorge's bibles, it's better to go with just an HPS but you are not a beginner. The HPS' lumen advantage is really only necessary once sugar leaves have popped out. IT DOES NOT INCREASE BUD SITES IN EARLY FLOWERING. in fact it will work against SOG growers b/c cannabis is super competitive and stretches/blocks out other plants in order to find the blue light. HPS is wrong spectrum but more power.
I have a vertical thread and a "trying to hit a pound with one 400W" thread on cannibis-world.org. You can find it if you want to check me out (under a diff handle) but that is only for your entertaiment and will not really impact what you are doing. A very experienced grower there (they all are) reccos using a mixture of HPS and MH. Interesting. Another very good grower (considered one of the best north of the border, in the entire country, by Marc Emery's guy) uses HPS exclusively. So what do you do? Well, neither guy runs high density systems and grow trees. If buddy number 2 only rocks HPS then MH isn't totally necessary unless there's an advantage. Well, in SOG (horizontal like you and my cabinet or vertical like my other work) small adjustments result in huge gains. These other guys veg for 2 or 3 months. We go a week so any little thing we can do is compressed and it's impact is magnified. The MH only switched to an HPS at 4 weeks (on an 8 wk strain) is just sucha thing,
peace