Hi, I have recently purchased an MP33 and also an MP30. I was surprised to note that the tension reccomendation on the rackets says that MP33 (16lbs) should be strung at a lower tension than MP30 (18lbs). I am confused because MP33 is a High Modulus Graphite and a stiff racket, where as MP30 has a graphite frame. By this logic, MP33 should be able to sustain more tension. Please advise...