Eat the weeds?

Can you eat weeds?  TPP has been asked this question several times during his long career, and that question has been thought about quite a bit.  First, the answer is that we do eat weeds, that is, some domesticated plants have their origins as weeds.  Second, a lot of these weeds have been around for a long time, so people have had ample time to domesticate them if they were thought to have any value.  Third, think about the difference between being edible and tasting good.  Here's the list of weeds that were presented as edible in an online article on Treehugger: wild amaranth, plantain, chickweed, mallow, curlydock, dandelion, purslane, clover flowers (warning: some clovers are toxic), lamb's quarters.  Now there are "grain" amaranths grown for their seeds, and even dandelions have some cultivars.  Generally selection is on extended juvenile stages, which in general are the more edible and better tasting.  If you grow lettuces and there are wild weedy species, lettuce begins to taste bitter as they bolt before flowering because the latex producing cells proliferate at this stage. 
Once years ago the Phactors tried New Zealand "spinach" because supposedly it stayed in an edible stage in the long days of summer and tasted like spinach.  What a good deal!  The plant is Tetragonia tetragonoides, and tasted more like freshly mowed grass than any plant we had ever grown.  It became pet rabbit fodder.  TPP thinks none of these weeds tastes good enough to be domesticated and if they had some redeeming qualities then people would have already domesticated them.  Otherwise TPP does not think these weeds will make up any significant part of any rational diet.  It may be good to know what is edible so that when society collapses, your friendly neighborhood botanist can earn his place in our new society.  Other than adding a bit of garnish to a mixed salad, a hoe is the best means of dealing with weeds. Mrs. Phactor found a recipe for "shrimp rampy" and it sounded reasonably good, but wild ramps while common enough in some places are not actually very weedy, and they do taste pretty good, as good as any oniony plant.  But foraging for an edible wild plant is different that eating the weeds.