LOL. Thanks then. :) So, thoughts? Obviously if WE are the 2nd time around, then there is some explaining required... I think it CAN fit in the timeline of how long we've been around, assuming all old technology has been eaten, and given that humanity and our technological development is such a SHORT period of time as far as the earth is concerned.
Nevertheless, there are positive points to making us the first round too, and developing a new world from scratch. This allows the odd tidbit from our era to pop in as well, which can be fun, if nothing else.
Personally, I think I appreciate the 2nd go-round more. And I don't think you would have to explain a whole lot. In certain settings, readers are just ready to believe. They are ready to make sense of it for you. Take JB's Codex. While some people pretty well know it is a lost legion of Rome on another world
, some would argue that it could be Earth, alternate timeline where Rome never truly fell, but changed hands when Gaius Uno learn to control furies.
No explanation really required and some people prefer it that way. It leaves them even more places to take their imagination (or argue about on forums :D).