What would be an acceptable method for wiring holiday lights for year round use?

The downtown area organization wants to have the lights year round but the wiring is single insulated conductors taped from lamp post to lamp post and then a plug attachment for the light to to plug into. Some of the runs have plug attachments taped together in the middle of a span.

Besides for the spans being over ten feet and the single conductors not being on insulators and the installation being installed for over 90 days it looks great. The power is originally picked up from a built-in receptacle located near the top of a street lamp post.

What would be an acceptable permanent setup?

Using some type of sunlight resistant cord or cable, installing a tension wire and mounting receptacles with weather-proof while in use covers to the posts or trees? Are any Christmas lights allowed for permanent installation? Does a disconnect have to be readily accessible? accessible? Or is it ok to use a ladder to reach the receptacle mounted about 12 feet above grade?

Is it ever ok to have a plug, male to female in the middle of a tension span? They are taped up pretty well.

Is GFCI protection required for this type of installation?

Any input would be appreciated.

Steve,
I learned the the way not to do it as a J-man in the past..

~Take 2 stands #10 THHN, color unimportant.. ~String approx 100' from mettalic light pole to metallic light pole ......
~Use the wire to tie a 'knot' to secure....
~Tap the conductors @ said knot for the pole ornamentation......
~Feed via 30A normal breaker....
~Wave to the AHJ as they go by.......
the state office is right downtown...

That sounds pretty much like what I am looking at. Except they used sunlight resistant, weather-proof, strain relieving, super adhesive electrical tape to secure the conductors to the metal street lamps. At least I'm assuming the tape has all those qualities--an electrician wouldn't use anything but....or would they? I'm sure they realized that the conductor scuffing against the metal pole might break down the insulation an liven the metal pole, making it possible for any passerby to get shocked from touching the pole...or did they?

were it me Steve, i would use ariel triplex, deadmen, ground the poles, supply a female cord cap @ each rated for the job, power via GFI, etc.