That is absurd. He's not saying "I have an idea, and with a bit of help we might reach extraordinary numbers", he claims "better faster leaner than everybody else".
Nice to see he's kept his word and following through as is the community. Really great and lovable group of folks. Sometimes there are cultural differentials, but everyone is really great and with a primary and essentially only rule of "be nice" - I think it's a breath of fresh air in this screwed up time.
It's not uncommon and no bad practice at all to fully specify a language before it is fully implemented. There were a couple of languages where the compiler took even many years to come into existence after the language was published, or was never finished. Other people - like e.g. me - develop the language specification and compiler in parallel. Just different ways to look at it.
How is it related to spec'ing the language. It's just fuzzy use of terms to appear extraordinary. That's all. Btw he still didn't answer my simple question, meanwhile everybody is commenting saying how nice the community is, how people should help instead of criticizing and deflecting the actual issue people had with the project.
You wrote a bit further up: "The problem is that in the initial releases the "high goals" were listed as "features" of the language". The "features" you mention are obviously the specification. Have e.g. a look at how long they specified Algol 68 and when finally a compiler appeared; CPL is yet another good example; actually at that time Wirth was one of the few who delivered a compiler simultaneously with the language specification.
I'd like to see the ALGOL group writing "we're faster and leaner than fortran" while writing their spec and no compiler to run tests against. I struggle to follow.
Something like this actually happened when they had to decide between Wirth's and Hoare's practice-oriented proposal and Wijngaarden's rather academic proposal. There was quite a bit of controversy about this, not based on true implementations. Big egos exist everywhere and in all times.