I'm sorry I did not read your whole post. These potatoes that grow every year are normal potatoes and you can eat them same as normal potatoes, because they are normal potatoes. I think I used the word normal a few too many times. Maybe they are fantastic potatoes.
An update, they are really growing well. This is the same potato plant, I call it number 4. I hilled them up a bit and mulched them, mainly with boxwood leaves. Box makes an excellent mulch. Hopefully if I keep them watered during the flowering, they will set seeds. I might try hand pollinating.
Odif, have you ever heard of Tom Wagner? if not look him up and look at all the TP seeds varieties he has developed.
An update on my potatoes. Number 4 again, it is growing really well, It is about to come into flower, so if I can just keep it well watered, the flowers may set seeds. I think I will give it some comfrey potion.
Yes, Mart. I have harvested many regular potatoes. I have also continued planting potatoes, so I will continue harvesting until mid October. I think my tsp potatoes have another month to go.
Well finally I was able to harvest my featured potato plant. I harvested 525 grams of potatoes from number 4. The other plants aren´t ready yet.
Update 2020. I took a photo of the seed bearing pods this year. After struggling to get potatoes to set seed for the last few years, I think I hit on the technique. This year I planted potatoes in pure compost and 4 out of 4 plants set seeds. I also will be sure to keep them well watered.
I read that in my area the potatoes don't get the seed pods often. They usually get them when July has been cool and wet, and we've had both.