I deep dug my borders this year just before the drought and had put in lawn sweepings fom the nearby cricket pitch. The clay turned even more sour and harboured gnats that gave me hell when I finally came to work the long neglected soil.

I tried some hedge trimmings (sticks and all) in some sections (Bay and Hawthorn; yee-owch!) Those were wonderfully gnat free and produced HUGE worms. Giants!

Obviously both forms of organic waste were acceptable but I will alway grab any bulky leaves for preference next time I double dig.

I will never bury lawn sweeping alone again that is for sure. Make sure you vary the type of waste you make the wormery out of if you are unsure.

I think the main problem was due to the grass compressing and forming a water clogged barrier.

Perhaps I aught to have limed it. But once you add lime to a clay, you change the type of flowers you can choose to plant from Acid lovers to whatever the PH becomes.

Not necessarily a bad thing but I haven't decided what I want to plant, nor what the situation will do best with.

one chap I know grows open-pollinate plants for organic seed production. He has 'a wormery' which runs like so:

about twenty feet long and six foot wide and about forty inches high. Elegantly constructed from ancient corrugated iron.

He operates a tree trimming business and puts the debris through an industrial mulcher, then keeps it in 40-50 litre bags.
He also collects plant material from the organic co-op - vege and fruit remains in varying states of rot. Small truckloads each week, then mixed with the tree mulchings.

(He also has a hefty cat to do battle with the rats...)

When it comes time to harvest the compost he moves the top layer to one end and waits for the worms to squiggle off to shady parts.

They're not garden worms at all. Tiger worms - red with yellow rings. If you leave a piece of damp corrugated cardboard in a heap of autumn leaves they'll be the ones that live in the wettest part of the cardboard. Shiny looking worms that are happy in the actively rotting parts of the wormery.

The lower parts of the wormery are deserted. All that's left is beautiful compost safe for direct use on the garden. When it's taken away some more mushy stuff is added and the wormery continues.

The other part is the stacking box affair.

If I had my time over I'd put in a spigot on the bottom box to draw off the water. It is seriously backwrenching to move the upper storeys to access the liquid manure.
I'd have a few more 'supers' - like a hive in full production.

If I had a system for partly rotting the material first I think it would be more successful. The tigers are there and working but I find the boxes are too small to take the household debris (and ours is a very small household.)

My mother has a big plastic compost bin into which she daily dumps the vege scraps from her small household. That bin is awash with sated tiger worms. They clump together under the lid and in the condensation given off by the rotting materials before squirming back to feast in the lower layers where other invertebrates and microbes/fungi have broken the materials down to sizes suitable for worm gizzards. The boxes just don't seem to have enough room for the various layers of corruption.

Perhaps something in the middle - and see if you can mechanise your wormery a little. It can be very heavy work.