Before I start, there's this compelling urge to spew inane observations like how sleepless nights are like bad relationships... because (complete the sentence)
"...like when you wanna sleep but can't"
"because... (whatever else comes to mind)"
Sentence completors (apologies, can't seem to find the verb form) are managers who either reverberate the final points of the discussion ad verbum, or acknowledges with a "yes" or "exactly" even though you're pretty sure they don't understand what you're talking about.
If you ever had to hire a sentence completor for anything technical, please for heaven's sake, reconsider. You may make the mistake of leaning towards Theory Y and thinking that hey, I have a great manager who really knows stuff.
Only to discover later that the Dark Manager knows DICK...!
Just like how a husband knows the back of his wife's... (complete the sentence)