"Its issued only to federal employees who drive federal vehicles for federal duty."
Sorry, but there is no such thing as a 'FEDERAL" drivers license. I have family and friends in FBI, DOJ and Treasury and NONE of them have heard of a FEDERAL drivers license!
Hell, even the military, driving much bigger and badder vehicles than you claim to have (a THREE year old car!!), don't have 'special' FEDERAL drivers licenses!! And maybe, postal carriers get these 'special' FEDERAL drivers licenses for when they get to drive the little jeeps with "all the bells and whistles".
I can see it now:
Officer: "Sir, can I see your license and registration?"
You: "I have this FEDERAL drivers license, and it gives me the right to drive ANYWHERE in the US with full immunity from licensing laws."
Officer: "Sir, can I please see a VALID drivers license?"
As for the Florida license, I have already provided PROOF that they only issue two types of licenses, either resident (FULL TIME) or "In Florida Only". If you do not live there full-time and have a 'resident' license, you are in violation of FL statutes.
"322.03 Drivers must be licensed; penalties.--
(1) Except as otherwise authorized in this chapter, a person may not drive any motor vehicle upon a highway in this state unless such person has a valid driver's license under the provisions of this chapter.
(b) A person who does not drive a commercial motor vehicle is not required to surrender a license issued by another jurisdiction, upon a showing to the department that such license is necessary because of employment or part-time residence. Any person who retains a driver's license because of employment or part-time residence shall, upon qualifying for a license in this state, be issued a driver's license which shall be valid within this state only. All surrendered licenses may be returned by the department to the issuing jurisdiction together with information that the licensee is now licensed in a new jurisdiction or may be destroyed by the department, which shall notify the issuing jurisdiction of such destruction. A person may not have more than one valid Florida driver's license at any time."
Source:
http://www.flsenate.gov/statutes/index.cfm?App_mode=Display_Statute&URL=Ch0322/ch0322.htm
'This non resident drivers license is for use only in the State of Florida. When you travel outside of Florida, you will be operating on your Out of State License. You will not be considered a resident of Florida, and may not be eligible for some rights and privileges of Florida Residents."
http://www.suwanneecountytax.com/dl.htm
Oh, and the reason that most (if not all) states restrict your having multiple state licenses is so that a habitual violator can't have multiple records in an attempt to avoid accountability.