Ahh the classic Christmas tree, beautiful but impractical. You could also try super cropping and get everything bent flat, I would do that after you top once though.
That's also an option on the possibilities list.
To make this relevant to the topic, I'm thinking about getting 3 Mars II 400s for the summer (indoors) grow, and figure shortening the height will facilitate penetration significantly. One per plant should be enough, I'd think.