Airplanes are certified with a 2.5-3deg/sec rotation technique at Vr.. .. .The effect at 10 degrees happens in most airliners, even in my FBW-scarebus. It is purely aerodynamical, and not built in to prevent a tailstrike.. . . .If your take off calculations are right, and you rotate at Vr with the given 3 degrees per second, your tail won't strike the ground. . .. .Even worse, if you apply your house-built rotation-technique, your performance calculations wouldn't be right, because the V2, the 35ft-screenheight point and your 2nd segment climb would be somewhere different than calculated.