-Some departure prodecures have name like "Lizard Two", " Nuevo Five". "Pizza Two" and so on. What do these number Two, Five, and so on represent on the title of the departure procedure?

-On a Loss Comm procedure leaving Clearence Limit.
If your Clearence Limit is where the Approch begins, you can leave the clearence Limit at your ETA, right? So if you have ETA of 12:30PM, You leave the Clearence Limit at 12:30. This is how I read the FAR.
However I don't understand the logic behind this. Why not leave your Clearence Limit (IAF) like at 12:10- 12:15 so that you arrive at the airport at 12:30??? Afterall ETA is Estimated Time of Arrival to Airport.

Can some one shed some light on this and tell me the logic behind this rule.

Thank you very much.