Riddle,
Had to go back and reread page 36 (and another 5-6 pages besides) to remember which post you meant. I'm still in the learning to read my plants stage, because things keep being contradictory (like the soil being dry but the plants showing no sign they are thirsty). I'm also trying to learn when they want nutes since they hadn't been given any until a four days ago. I know my lack of experience is probably making me worry more then I should, but I don't want to kill any of them by not being worried enough either. Try to bear with me- I do learn quickly, but the information from you and UB is scattered over so many pages that I can't always find what it when I want to.
My logic on the nutes went sort of like this. Nine days ago I gave the girls a shower, and they reponded about the way you said to expect and put on a big growth spurt. But, they are still relatively small to wick it up fast and the soil 2+ inches down still felt a bit moist 4 days later (though the top 2 inches were bone dry). I waited an extra day (4 days ago) and gave them a decent drink with 1/2 strength nutes at that time. Now, since the half strength nutes didn't burn them and it looks like the plants are developing a deficiency it seemed logical to me that the my girls needed more then 1/2 strength, which is why i was talking about full strength last night.
Frankly, I'm still not sure I understand exactly how you're timing your feedings and rain showers. It seems like you are making it rain, letting things dry out a bit, then feeding, waiting for it to dry out a bit, making it rain, etc, and you're doing a step every couple of days. I understand your plant is bigger then mine and drinks more/wicks faster, but how can you be sure you don't have more moisture down deep then you think you do? So far the only time my plants have started to show any signs of being thirsty was when I let them go 5 days without a drink (that was the day I made it rain), so I still haven't gotten an exact feel for how long their cycle will be. I was thinking about making it rain today, but with them showing nute problems I figured it was better to give them a few cups of water with nutes before I made it rain again. Btw, my girls are still vegging (day 19 since they were transplanted). I know you said doing this to plants that were vegging would create trees, but since thats my goal anyway it made sense to go ahead and get started.
Let me see if I can share a bit more of how I have learned to read plants
but first as to the watering, you don't want your soil/medium to go completely dry. This was one reason I suggested using a scale to actually see what was happening. once you use a scale several times you learn just by picking up the pot and feeling the wieght, some say just feel the wieght of the pot but without first using the scale and doing the math as to exactly what percentage of water is there you are taking a chance on letting it go to dry
One of the things I can share is that when I was in veg it generally took 5 to 7 days between waterings, a big part of this is the humidity we are told that some where between 40 and 60% is good for veggin with most shooting for somewhere near 50% this slows transpiration quite a bit which causes the longer intervals between waterings. I have yet to try experimenting with lowering the humidity during veg to try and increase transpiration rates as I don't currently have room to have trees happen
I described that when it rains the plants droop and most all of you have seen this, what I did not describe was what relaxed looks like and how to tweak it. Perhaps it might be a good idea to have everyone lurk in the problems forum and just look at some of the pics of plants in trouble. There are extreme cases that show the little serated edges of the leaves pointing up, the leaves themselves are erect (opposite of drooping) like standing up or reaching for the light. This is what it looks like when the plant is transpiring hard and is a lot of stress (opposite of relaxed). When they are happy and relaxed they simply kinda hang out in the middle between droopy and erect. I have seen pics where the top 1/3 of the plant is erect and the bottom is relaxed (they are kinda funny pics) and all the grower would need to do is raise the light an inch or two till the top relaxed as well (could be heat from the light or too much light or combo of both) When there is enough light they will turn towards it and bask in it, I showed pics in my journal where the leaf curled to face the T9 and it was right on it touching it, just happy as hell
Your goal as a grower is to create that perfect garden enviroment where your plant is always happy and relaxed with no stress (or as little as possible) your tweaks should not be drastic,,,,,,,as this will affect all other elements. If you add light (hey everyone says more is better) lets say you have 6 cfl's and decide I'm gonna finally get that HPS oh yeah I want bigger buds, so you add it and things change drastically, leaves start to stand up go erect reach for the light, the inexperience grower will say now that's what I'm talkin about look how much more she is likin this new light,,,,,,,,,,WRONG, she is stressing and by the way this is what most growers do, they ram as much light down the plants throat as it can stand without burning and think they are good, they only pay attention to the basis of temp & humidity with out considering the effect. They are more concerned with smell and temp control when it comes to ventalation than with giving the plant fresh air. I leave a window open in the winter and adjust my heat to compensate (for my comfort as well as the plants, set to 78, while temps in grow area are 72) I understand how simple convection works so I know that cold fresh air comes in that window and heads straight toward the floor, so my fan is at floor level and aimed at my light (not my plant) the cooler fresh air circulates in my grow area giving the plant fresh air (CO2) and cooling the light so it can be closer (as needed). Hell there are so many folks that worry about how much a freakin light will add to thier electric bill I can just see em thinking there is no way I'm heating the outdoors, but I don't give it a second thought, I know what the plant wants!
Once you have the light set right where plant is relaxed you can tweak temp & humidity (using the heat index as a guide) increase the temp by a degree and watch, add another as long as the plant stays relaxed your good, record these numbers for future reference. same with humidity 1 point at a time till you see ANY sign of stress. Your goal should be to achieve fast transpiration while plant remains relaxed (leaves just hangin out, basking in the light, happy) The more you can make it rain and feed the bigger your plant will grow, the bigger your buds will be, this is what you are after and is what a perfect garden will do!
gonna keep looking but i think im good long as i can keep my rh down 
