Zwift powerzones bit to high and how to not overshoot my workouts

for example when you have an FTP of 200w endurance training must between 112W and 150W max.
The workouts in zwift says endurance @ 145W.
So when you have an external powermeter its very easy to shoot 10w over or onder on erg
mode.
What i do is i correct my bias from 145W to 130W makes al my power lays between 120W and 145W.

Much more in line with my hf also in endurance zone than.
I do the same for al the other zones.