When you connect to your favorite MMO, etc., it's doubtful that you're using the HTTP protocol to do so.
Still useful, but for one of many "Internet"-based scenarios.
TCP probably has higher overhead, but even that is going to be next to nothing unless you've got packet loss
traceroute on UN*X uses UDP by default. There is no overhead when using UDP.
ICMP Echo, I'm not sure about, but I don't believe it has overhead, but as I said, it is a depriortized and possibly rate-limited by routers.
HTTP 1.1 and 2.0 do not require TCP, although that is by far the most common way they are used.
What overhead would TCP bring after the three-way handshake on a uncontested stable network without packet loss? I would expect it to be no more than UDP.
> traceroute on UN*X uses UDP by default. There is no overhead when using UDP.
You are correct. UDP will get you lower numbers, I was more of saying that TCP will not be much worse (maybe within 1ms) under good network conditions.