The way I'm picturing what you describe has my thinking such that your branches will be on the ground with even a minor load of fruit. They'd only have 4' to go.
You could trellis them but that would make it hard to mow around with it being in a circle.

My presently (non-espaliered) horizontal branches are not horizontal without fruit and by the time it's said and done they will be angled down at the tips as much as they're angled up with no fruit.

Horizontal is good for producing fruit early and making strong crotches for old limb structure. It is not good for bearing weight low to the ground without support until it gets large.

Do the horizontal for your crotches and then let the branches angle off and you will have a strong structure that won't need to be supported to keep it off the ground.

My "Alderman" has a very weeping growing style. The branches that have fruit, the tips are touching the ground and the rabbit has been trimming them. I do like it a lot more then my "Superior" that seems to want to grow up and up and up. I've had to prune some very low branches that grew this year. New growth on top may have to be pruned out?

{{gwi:119715}}

My pruning book says to form a plum to a "pyramid"...

The main reason you don't want horizontal branches is that you will soon have vigorous shoots heading straight up off those branches. You will either need to prune them out or within a short time you'll have an odd looking tree not at all like you intended. If your branches head up at between 30 and 60 degrees, you will eliminate most of the upright shoots. This will give a strong tree with less fruit hanging down like Frank's plum.

Frank: This plum and your earlier peach indicate that you aren't pruning enough. You need to shorten those branches so they grow stiffer. The plum has a small crop and is still on the ground.

The Fruitnut

It depends on the ultimate size of the tree.

Trees that will become quite large, such as apples on seedling rootstock or semi-standard rootstocks like M.111, should be pruned with rings of 3 scaffold branches 18-24" apart vertically. For dwarfing varieties, you want the branches somewhat closer together, 9-12".

I've seen some very productive commercial orchards with scaffolds nearly horizontal though most people seem to try for a 60 degree angle from vertical.

Can you prune a plum in August?

Frank's long nearly horizontal branches display what I was warning about.
It's fine if you support them forever or if fruit on the ground is what you want. You probably won't ever break a branch because all the weight will be off the branch long before it gets to breaking point. But critters and disease will be a problem.

Even semi long stretches of horizontal require quite a few years of support before they can stand on their own.

Personally I would get the good crotches established and let them go. Maybe spread lower branches on a big tree a little more so they're out there getting light.
But as for spreading whole branches to be free standing, the fruit will do that and eventually you end up pruning it off because it stays in the down position and that's not supposed to be the best for fruit production. (I haven't found that to be the case, I think the production has to do with the branch that comes out of the bend. I think what I read wasn't worded right and once the upward branch is dominant your fruit production falls on the downward branch. Once it's dominant is when I prune the downward branch back so I wouldn't see a fall in production.)

There are so many possible ways to train fruit trees. The christmas tree shaped central leader is now the most proscribed method for free standers (M26 and on up). It is a relatively efficient shape for harvesting light throughout the tree to get the maximum yeald of maximum sized fruit.

The funny thing is that the home orchardist often doesn't need to maximize space and harvest. The christmas tree (the academics call it pyramid) shape is not the easiest to maintain. Once branches get overloaded with fruit and bend below horizontal you almost have to replace them to maintain the efficiency of the shape. As mentioned, some varieties just seem to want to weep. Ginger Gold is the one that breaks my balls this way.

Also, with this shape the upper scaffolds must be periodically removed once they get to be too large diametered. I believe that very few hobbyist ever really master this part of maintenance.

Shaping a tree like spokes would be fine, although I agree that it would require support for a few years. It's actually just an open center shape. I think you are imagining a tree without secondary and tertiery wood. You are really better off with just 3 spokes for most varieties of apples- maybe 4 for plums and apples that spur up a lot and dont produce a lot of secondary and tertiery wood.

The only drawback of this horizontal, open center shape is the requirement for support.

The easiest shape to maintain in my opinion is an umbrella shape. Once you make the shape all the decisions are easy-just prune to the weakest wood to create a weeping shape. Trees are productive, tend to annual bearing and can be maintained at a height above deer if you want, which makes mowing easy also. It leaves room in the yard for other things. You have to like the ladder dance though.

That said, I usually train trees to the before mentioned christmas tree shape. Not only is it efficient, but the fact that it requires skillful pruning ensures that I will always have lots of work.

Thanks to all for the recallibration!!

Bart