@Miguel > You shouldn't have to move your EQs anywhere really outside the 12 o'clock parameter. I'm not sure why you friend believes it is necessary to increase the EQs to 100% but its likely he is experiencing distortion / clipping at those levels. Does his VU meter run into the red? Yes? Well thats bad.
Mixing tracks is slightly different in that you may wish to choose to remove certain frequencies from the mix - the Low EQ / Bass being the most common as two bass lines can sound a little muddy.
So yes, to answer your question, I start with my EQs at the 12 o'clock position and move them from there as necessary (but I rarely have to increase them).