Ok, I thought so.  I had come across this MC version:

-------------------
Name: Installer-Core-fbs.385
Author: fbs
Time: 17 November 2013, 9:54:59.988 pm
UUID: 363eee87-69f1-664a-857c-0ba322add113
Ancestors: Installer-Core-cmm.384

I think this is a serious misuse of DNU, but this method is, in fact,
used: the #isThisEverCalled: pops up a self halt which breaks
Metacello.

While we should rewrite this to _not_ need the DNU, we need the
#isThisEverCalled: removed.
-----------------------

and it made me wonder if Metacello could arrive there, whether it
would be broken now..

On Mon, Jan 6, 2014 at 5:54 PM, Tobias Pape <Das.Linux at gmx.de> wrote:
>
> On 07.01.2014, at 00:43, Chris Muller <asqueaker at gmail.com> wrote:
>
>> Does anyone know whether this is used by Metacello?
>
> Metacello uses Gofer :)
>
> Best
>         -Tobias