If the effective tilt of antenna is calculated as
Effective tilt= Electrical tilt + Mechanical tilt
And electrical tilt has the range from 0 to 8 degree then,
Isn’t it will be a wise to give preference to electrical tilt for all your requirements of tilt ranging from 0 to 8 degrees, as the same has ease in implementing. I mean just a turning of knob will do it as compared to the loosening and fighting of mechanical fixtures/nuts/bolts for the mechanical one.