Thanks mate im glad your enjoying it, no I don't think your wasting your time, lots of people will do this, but maybe I could make a suggestion. Why not cycle it some thing like this, heavy day followed buy a lighter day, for example Monday is leg day so our squat session would look like this,
Warm up135x15
205x10
205x10
225x7
245x7
265x4
280x1
On the next Monday it will look like this,
Warm up 135x15
160x15
170x15
180x15
190x15
200x15
This way you getting one heavy day which will help build strength, then the next leg workout your going lighter contracting the muscles and giving your tendons a rest from the hammering they took the previous leg workout, this should help prevent injuries and keep training interesting as its constantly changing, weights given where only a guess and im sure you will adjust poundages to suit.