Temperate climate "comfrey circle"

Did I just invent this? Do you think it would work?

comfrey circle design

The idea is that I could throw any weeds into the depression in the centre, the comfrey would
a) act as a barrier to prevent them spreading out of the hole and
b) use the nutrients to grow and make mulch material or greens for liquid plant food.

I have grown banana (!) but they did eventually succomb to the frost (and weren't fruiting plants)

What other plants might be suitable for this sort of arrangement?

Just today I propagated comfrey around a raised bed for much the same reasons.
My raised beds are filled with half composted materials, and the comfrey is there to capture and cycle nutrients.

I put beds like this next to every tree I'm trying to feed.
Its a way to create a reservoir of nutrients and moisture.

A circle of elderberry live stakes could be interwoven with vines and the resulting enclosure filled with compostable material.
This is a version of a willow poop beast, one that skips the poop and grows edible plants

Figs are supposed to do well in these circumstances, according to this thread:
https://permies.com/t/46085/composting/Growing-compost-pile

Of course, squash is notorious for loving unfinished compost, but that same thread mentions tomatoes.
I've seen grass fed corn do quite well, so that's another possibility.

Interesting idea. I reckon you'd want Bocking 14 specifically so it doesn't seed into the middle and compete with whatever you're composting. The only thing I'd wonder about is how quickly the roots colonise inward, comfrey is pretty aggressive underground too.