[Scion9066]

But that would mean Google would have to send some kind of signal to Google's servers that you're using Incognito.

Imagine the headline:

Chrome tells Google (and only Google) when you're using Incognito mode

I'd imagine people would be even more pissed that Google is making it detectable for themselves and not others and would accuse them of being anticompetitive, even if they used it to turn off tracking for those users. They certainly wouldn't be able to turn off tracking like that for users of Private/InPrivate browsing on other browsers.

[TheCoelacanth]

They don't have to call the feature "Incognito". If they can't deliver on what they're promising, then they should call it something that they can.