> but often can reach 900 Mbps up. Typical is 500-600 Down, 900 Up; the highest I've seen down on e.g. fast.com is 900 Mbps
Typical observed speeds down, which is what everyone cares about for residentical internet, are 500-600 Mbps — far below 1Gbps. I mentioned the outliers for color but they're either not useful to me (I don't need 900 Mbps upload) or not representative of real service delivered (I've only observed 900 Mbps once; as I said, 500-600 is much more typical). Off-peak is typically around 700 Mbps down.
So I still don't know what comment or point you were trying to make by claiming GigE TCP can only reach 940 Mbps. It clearly isn't a counterargument to my claim that Centurylink's $80/mo, residential "gigabit" fiber offering does not deliver 1Gbps internet service (nor would I expect it to).
> Typical is 500-600 Down
500/941 vs 500/1000 is 50% vs 53% of advertised. The 3% isn't really significant. I don't think it's bad service for the price, but it certainly isn't true 1gigE.