hmmm *scratches chin* of course it is possible, I'm not sure if it is possible for you, though. Your vert is 22 inches. That's not terribly advanced or anything, so there is a great room for imrovement. 9 months is roughly 36 weeks (4 weeks a month). 17 inches in 36 weeks is like a little less than half an inch a week. I'm not sure when your gains will plateau. I'll say anywhere from 12-15 inches is very very realistic, but I'm not sure about 17 inches. That's not a negative "not sure", it's really that I'm not sure, I don't know.

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