Lately, in contests, some fraction of stations seem to respond with half a second delay, or longer. Could they be remote stations?
What is the minimum delay over internet with good connections and fast computers?
What is the maximum real delay when the operations seem smooth?
That can also be multi-op stations who are interleaving running and S&P on the same band. They call you, you send the report, then there is a long pause before they respond. I got several of those in the CQ160 CW contest. Sometimes it gets annoying: one big east-coast station called me three times over about 15 minutes before they got the timing right in order to reply!