This is one of the reasons Telebit did the whole UUCP "g" acceleration 
in the Trailblazer/Worldblazer modems.

The turn-around time for the small packets being acknowledged was so bad 
over normal modems that it was painful.

So Telebit made the modem do the acknowledgements (IIRC), stream the 
data over the phone line, and the receiving end would "play along" on 
the acknowledgements.

It was very effective for news especially.

On 3/8/2017 5:03 PM, Joerg Schilling wrote:
> During that "modem" time, I started with a 2400 baud modem and soon 
> upgraded
> to a US-Robotics modem. It turned out that UUCP had several issues and was not
> very effective with high speed modems.
>
> ...SNIP...
> Jörg
>