V speeds insertion...
IMHO, it was a V speeds-related incident, like someone was stating earlier on, tail strikes of this magnitude on rotation are most of the time related to early rotations at high TOM. I know that, back in the MD80's era in AM, dispatchers used to present the cockpit crew with the V speeds and the crew would cross-check them again with a "quick reference table" according to a specific flap setting. Is this practice a safe practice? I dunno...I guess it does cater for a "double cross-check" of the speeds provided someone does cross-check them...
My 2 cents of opinion