[amiga386]

That it may be there or not doesn't mean it "caused no harm". It sounds like yet another carbuncle added in haste and then never fixed properly, leading to 6 years of fear of touching it.

If it's truly intended, it needs to be part of the official spec, with a robust justification of why it's there at all. Neither server nor client ought to have unnecessary and undocumented things "just in case", because that breeds a culture of uncertainty.

If you fear client regressions, make it a mandatory part of the client's test suite. You control the client, right?