[Brightcolours]

If you have 9 lenses that focus fine and one lens that needs microadjustment, you'd pretty much have to either shim for that particular lens or get another copy, if you wanted to do manual focusing inside the viewfinder. 

 

Also, adding this form of negativity to the end of every message is generally considered to be being a useless asshole who thinks they can make their argument stronger by insulting the other party. You may not think that but everybody sees it that way so it would be really beneficial to your quality of life if you stop doing that.

That is nonsense. A lens that needs microadjustment either does a wrong final step with PD AUTO FOCUS or has one colour which focusses on a different plane which the AF sensor picks up on.

 

Neither has anything at all to do with the focus screen, or the imaging sensor.