Hi just re-read the original thread and realised what I was suggesting is already the case.
So basically I agree with Woody and dont really see a problem.
Take this example
http://forums.civfanatics.com/showthread.php?t=281621&page=4
This Battleship/Trireme example is just an extreme example where the Patrol function is a bad choice.
Then take the same map with the 3 fish resources, but this time you have 2 Frigates and the enemy 1 Frigate.
If you have both your Frigates on 1 resource each the enemy can definitely pillage one and might be able to get away or if you attack him next turn he gets a defensive bonus.
However if you have both Frigates are patrolling then the first Frigate gets a defensive bonus and might be able to destroy the opponent without the resource being destroyed. If he loses then the enemy Frigate is unlikely to be able to successfully pillage the next resource with out being destroyed. Or you will then be able to destroy him next turn.
In this case patrol works out better. Same as any Civ IV feature plus sides and down sides I vote to keep as it is. You just need to be aware of the possibilities hence the civopedia needs to be improved not the game mechanism.
Ok when Patrol goes wrong goes it goes very wrong, but this is similar to other Civ Mechanisms.
Often a stack attacking an enemy city really has problems until enough collateral damage is done and then the opponent can easily destroy the remaining unit sometimes on 99% probably getting a load of experience points for not much.