So two recommendations:
1) Add a trap for "ConnectionError", and
2) Have the "connection refused" message display at a frequency lower than the server poll rate. I'd even prefer an email once option--"Hey, your server's offline."
Well, the error is trapped which is why you only see the details when debug is on, but I think you do raise a valid point with there being no need to notify of every attempt... I'll think about how to do that, though, since you WOULD want it to report on failures outside of the status poll (since it would likely indicate a command failed). I like the idea of an event or notification or something for when it thinks the server is unavailable. Maybe a "Server Offline" event that is fired after it can't reach for XY number of tries/minutes or something? Then as an Indigo user you could take whatever action you wanted - email, push notification, etc.
My plugins that have a persistent connection (i.e. network sockets or serial connection) use a scheme where they back off the reconnection attempt, so they already won't throw errors every 20s for 8 hours... so I like the idea for the http API devices. Thanks for the suggestion!
(<durosity_voice>BTW, I'll expect a patch from you to solve this by tomorrow morning. thanks.</durosity_voice>)