Interesting discussion going on.
I started wondering about this: If you only save the seed from one pod, and repeat the same year after year will the inbred seeds become weaker as they lose genetic diversity? It may not be a problem at first, but after multiple seasons it could weaken the crop. Pure seed is all well and good, but it would probably be better to grow multiple plants of the save variety together, save healthy pods from multiple plants and mix the seed together. In the single pod isolation strategy, you would have to make intentional crosses between siblings, a real pain. This may be why Dr. Bosland uses cages. I'm assuming there are many plants in a single cage, but I haven't found the article online to confirm. This is probably very tough for hobby growers like me who prefer variety vs. multiple plants of the same type.
In my garden I save seed from plants out in the open. If it crosses great. If I lose something as a result hopefully I can go back to the prior year's seeds or find seed from somewhere else. If a plant is just so great I'll try to share seeds and also try to keep it alive perhaps as a clone. I haven't yet gone to the trouble of bagging or gluing individual pods because it's extra work and isn't guaranteed to be exactly the same as the parent.
If I was in the seed business for profit I'd have to bite the bullet and go with cages. Unfortunately, I'm not.
Lastly, I'd never complain if I get accidentally crossed seed from a member. Just don't mislabel or send me a seed borne disease.