Yeah, I expected a large ServerHello, but then I would expect the server to send Seq=[LargeNumber] packets. Often you'd get an ACK for the ClientHello, then a missed packet or several, then the final packet of the ServerHello which is often small. Or at least an ack from the resend of ClientHello with a large sequence number.

I guess I've seen pmtud issues way too often in my life, and I just jumped ahead. :D