image 1: no sailors- 44/59
image 2: Engie on support slot- 43/62 ok normal.
image 3: Engie on BO slot- 43/62 there you go.
image 4: Engie on T- slot 43/58 but we already know that.
This is less important with Engies in the BO slots on the 5% of ships but more as BO
with engine ability on the BO slot for said 95% of ship you mentioned.
Also if you want to take the scientific approach, theory holds true until proven false.