Growin' like weeds!
I was working in a part of the garden with my most mature Miscanthus clumps today, and was amazed at their growth.
It's M.s. 'New Hybrids' started from seed in early 2004. I trimmed them to 4" exactly 2 months ago, and they are already over 3' tall. This must be the 'third year leap' you hear so much about. They're already doing their wind-screening of the veggie beds, after only 2 months.