Totally agree about the fan and the silica, but there are still times a stake comes in handy. For example, right now I'm running a pretty poorly managed SOG, 26 Albino Rhino, grown from seed in coco on a pheno hunt. Since I was starting with 50 seeds, I knew I was going to have several different phenos, but what I wasn't really expecting was what a wide variance I would have in the phenos. I have 5 dictinct pheno types, 3 of them strongly sativa and 2 very indica dom.
So as you can imagine, I've got quite a difference in height between some of the plants. The indicas are behaving themselves very nicely at around 4 feet per plant (including pot), but some of the sativas are well over 6 feet - or would be if I didn't tie them down. I know, I know, but shit - it was my first coco grow, and I had no fucking clue how they were gonna go all Jack and The Beanstalk on me. They just friggin' blew up in about 2 weeks' time.
Anyway, I have the sativas trained and bent over, but some of them are getting enormous buds. We're halfway through Week 7 and I have one top bud that's about 15 inches long, and another that's 18 or so. Both of those plants are so budheavy, they lean way to one side. So I stake them up to keep them upright, or they would be snapping.
The indicas are stout and stocky little mofos, but some of them still have a tendency to lean a bit because of the heavy top bud. Not to a dangerous degree (they're not going to fall over or snap), but enough that they cast a larger shade footprint than I want. Staking some of them helps keep them perfectly vertical, and keeps their shadows from falling over nearby plants.
I'm embarrassed to do it, but I'll post a few pics. The first one shows a couple of the big sativas, tied down and bent over, and staked up to keep them from falling. The second shows one of the indicas, with a top bud about 11 inches tall at the moment. I just wish this fucker would frost up more, because she and her sister are lagging way behind the others in trichomes at this point. Other than that, she's my favorite plant. And, the third one is that plant's sister in the right foreground, with some skinnier indicas in the background staked to keep them perfectly vertical. If you look in the upper right center, you can see one of the sativas from behind, tied down and staked to stay upright.
Like I said, I'm not proud of this grow at all, but fuck... it's a pheno hunt, so I just grew out all 5 phenos to see how each one turns out in the end. This run isn't really about yield or making the cover of High Times; it's just finding a good mother or two to go forward with.