In that case, I might have misunderstood the intent of those examples.

However the difficulty of understanding also illustrates the increased maintenance burden and language complexity.

Unless workarounds to a missing feature have a higher maintenance burden like in this case, and you can't avoid it via learning

Go's preferred way would probably be something like compute the aliased operations on the line(s) before, then reference the final values.

E.G. Adapting https://github.com/golang/go/issues/34174

    f := 123.45
    fmt.Fprintln("value=%08.3f{f}") // value=0123.450
    fmt.Fprintln("value=%08.3f", f) // value=0123.450
    s := "value"
    fmt.Fprintln("value='%50s{s}'") // value='<45 spaces>value'
    fmt.Fprintln("value='%50s'", s) // value='<45 spaces>value'

The inline {variable} reference suffix format would be less confusing for situations that involve _many_ variables. Though I'm a bit more partial to this syntax with an immediately trailing %{variable} packet since my gut feeling is that special case would be cleaner in a parser.

    fmt.Fprintln("value=%08.3f%{f}") // value=0123.450
    fmt.Fprintln("value='%50s%{s}'") // value='<45 spaces>value'