Apology to Tomato Forum Folks for posting before reading
what you've written:

If either of you (Harry & TwinHerder) still have questions about tomatoes, possibly my reports on the tomato test on the vermicompost forum will have some further information.
Another, not GW site, Tomato Dirt was useful to me.
My thread was titled How To Use Castings.

Here is a link that might be useful: Tomato Dirt

Thanks for the extra info.
Were the plants that had BER more root bound / in the smaller pots?

Im working on the theory that something prevented the buffering of the soil from rebounding from a ph change. Once things root bind in a container it is very easy for them to be exposed to pockets of soil that have no buffering agents distributed in them, and worse still, may have a pocket of low ph materials.

I had a tomato plant that had BER on one stalk of the plant... at the end of the season I tracked its root into a unbroken up clump of peat... opps

TwinHerder,
wow, tracking it down to the roots! Sounds like some sort of CSI tomato investigation you had going on!!
Actually no, the BER didn't just occur in the smaller pots. In fact I think the first one to show any BER was on of the Early Girls in the 5 gal.pot. Only a few tomatoes on that plant had the BER and I was thinking it might have been do to drying out too much between waterings. Wish I had a drip system.
Harry