No vegetative growth at all

I have 50-odd varieties on several different rootstocks, (but mostly Ottawa-3 at present). A number of the older (10 - 12 years) trees have "runted out", (is that the correct terminology) - every bud on the tree has become a fruit bud. Over the past few years I have tried to stimulate vegetative growth by heading some of the vegetative growth, (dormant pruning), which, if I understand correctly should stimulate the buds just below the cut to sprout and make new wood. It didn't - the buds below the heading cut turned into fruits buds, so now I have trees covered in fruit spurs, but not an inch of new growth. (This sunk in to my consciousness when I tried to cut scion wood for my grafting workshop later this spring. There is nothing to cut.)
Now, a case can be made for this being a "good thing" - drawing from the espalier model, every fruit bud has at its base 5 leaves, which provides 5 times the photosynthetic potential of a single leaf bud. Is this complete nonsense?
Is there a case to be made for drastic, major surgery - cut the scaffold branches back to stubs, to provoke a flush of vegetative growth, a sort of catastrophic renewal pruning? (Presumably best done over more than one year...)

Broomholm Orchard
Zone 5b in Nova Scotia

That is interesting, David, but isn't it the fate of a dwarf rootstock to stop growing once it has reached its final size?
And after all, a fruit tree should be producing fruit, not wood...
This reminds me of a conversation I had with Bill Mackently (the former owner of St-Lawrence Nursery) who was saying he managed his orchard to produce scion wood, and no fruit, but he nevertheless had fruit, which was sort of a pain for him as he didn't know what to do with so much fruit!
I also have a few trees on Ottawa 3, but they haven't reached that stage yet.
Claude

Jolicoeur Orchard
Zone 4 in Quebec

This would indeed be a perfectly desirable situation if the trees had produced a reasonable canopy. They didn't. They produced the beginnings of a framework - the first tier of limbs, (although, often only 1 or 2 branches) - with no further branching. So I have ended up with one or two bare limbs with hundreds of fruit spurs, or short stubs of side branches ending in fruiting spurs, with a long central leader lined with fruit spurs and no further branching. I followed Michael's injunction to "leave the leader alone" with dwarf trees, but even if I amputate the leader, all that happens is I am left with a stick in the middle covered in fruit spurs, with a lopped-off top. In other words, heading cuts are not followed by stimulation of vegetative growth and branch development below the cut - they just result in a shortened branch or leader.
This does seem to be at least partly cultivar dependent. Two trees of Tolman Sweet , (as well as a number of others) have behaved like this. But a couple of trees of Fauxwhelp which I top-worked over to Sweet Coppin and Brown Thorn produced exuberant growth of both the understock producing suckers and the newly grafted material branching enthusiastically in response to heading.

Broomholm Orchard
Zone 5b in Nova Scotia