Espallier apple trees

I'm thinking about experimenting with espallier-ing a few apple trees along the south side of my garden. THere is a 9 foot fence already in place to do this, It's two rolls of hog wire high--so I have that to support the tree on(I would plant the trees at a t-post or wood post point of the fence.

The trees would be in full exporsure to prevailing winter winds from the south--since the apple tree is on a plane instead of a globe woudl this be an issue? I'm at 1000 feet so the wind is just "more". But then the fence would help support it too. Any issues with exposure if the trees aren't against a mass or are not in their natural form?

Also since this is on the south side was thinking the shadow of the tree would be "airier", and having stuff planted on the north side would be less of an issue.

Any issues to think of? how long did it take to get the tree to its form? Can you pick a tree that can be pruned to the appropriate spaced 6 sideways branches(or 4) and gently train those on the fence, or do you have to cut the tree off and start everything from scratch with new shoots?

Actually I have room for five trees to do this, I am also training two grapes on the fence(I wouldn't put the apples where the grapes are).

ps, thinking of doing more of a fan shape than a tiered--more "natural" looking, just cuz I like that

and there are no light issues, full sun for at least 8 hours, probably more like 10

on a south facing fence it should work out fairly well, can't wait to see photos when it is all done and growing

No real problems that I can think of, I planted 3 apples, 3 pears, a plum and a plumcot here at Rose Villa on a two rail split rail fence just a year and a half ago. That's 8 trees on a fence 80 ft long. I had some aphid problems on a couple of the apples, but that was easy to deal with, squished them with my fingers. Already have some apples and pears coming along, not many but then the trees are still new.
Planted strawberries under the fence, just last February and they are already producing lots of berries.
This is just south of Portland, just several hundred yards above the Willamette river so my climate is not quite yours, but the fence faces south and gets full sun.
With a fence as tall as yours you could do some really fancy espliering.

  I have thought of constructing some short sections of strawbale walls to espallier some trees on. The wall should work as a heatsink in my climate. If I placed a slightly wider top on the fence I could drape a spun fiber protective layer down in the early spring. I've built one wall similar to what I envision along the patio but haven't put any plantings against it yet.