I have always wondered about this, why r most engies stupid.
and this is why i think they r.
when i follow an engr when i am in limbo i always see the following thing
engie plants a mine or fixes a CP, then runs off to another objective as he arrives he find that his powerbar is not really full but still he starts 2 build. a few seconds later his powerbar is emptied by a still unfinished objective. so he keeps waiting with his pliers in his hand and pressing the Fire button like mad , hoping that the objective will be finished sooner. 2 seconds later u hear a highly pitched noise,followed by the deafening thump of a panza being fired towards the engies panties, SPLAAT
morale of this story
if ur powerbar is empty , get away from the objective and wait with ur gun in ur hand .
the only engr ive seen doing this is Dave the Duck, So u understand why most engies must be plain stupid