>> There is no need to calculate anything with the 
>> "start-display-at-beginning-of-minibuffer" solution I sent a few hours 
>> ago.  Emacs does everything for you, at no cost.
>>
>> Or is there something that you need (e.g. for Eldoc) and that this 
>> solution does not do?
> 
> I suppose not, but I take it that that solution is a non-starter because 
> of Eli's and Stefan's objections to it.
>

I did not see objections from Stefan.  And the objection of Eli is only, 
AFAIU, that in a longer term a better solution should be implemented.