How firmly should it be?

As I mentioned before, slight toe angle adjustment invites change of camber value because the frontal axle is suspended applying "Steering Axis Inclination" SAI and Caster Angle. So the change of hub surface causes not only the purposed one but also another setting value, camber inclination and scrub point.

These change doesn't cause the physical property on front but also does on rear axle setting, geometrically and interactively with frontal hub three dimensional position. Trifle tampering invites irreparable result for sensitive auto-driver?

All of the users do not always accept the different result, getting accustomed to the changed steering reactions?
Consequently, a trifle to value change causes unexpected tremendous change in the wheel alignment! The alignment is all interactive one on earth.

What I described above means the wheel alignment never be carried out only one trial, the change of hub position calls that of thrust angle, and the change of thrust angle invites the steering centric position, the adjusted steering wheel returns to more corrective position.

The attempt on the adjustment should be repeated several times if the alignment should be desired so firmly as to ideally completion.