Wow... Thanks guys. This helps tremendously. The typical scenario that I am running across is... Outside the mobile homes is a meter and 100 Amp Breaker/Disconnect. The homes are than fed with 4 conductors to the (now 100 amp sub panel) inside the homes. Due to lack of spaces, ( usually only 12 circuit Federal Pacific panels )... the 10-3 UF was installed directly under the main breaker lugs along with the #2's. It is than ran (without physical protection) under the mobile homes to the (sometimes) fused A/C disconnects. Now you have 20-30 feet of #10 AWG wire (un)protected by a 100 amp breaker. I was almost 100% sure this was NOT code compliant.