Most of my fresco work has been done on old Italian walls, so my panel work has been limited to terracotta tiles. I've seen tiles laid inside wooden boxes(1" thick), chicken wire was fastened over this to hold 1 layer of arrechio. The intonaco was applied over this.

The panels seemed to hold up pretty well. Is this overly simplistic? Does it last? My presentation is only 2 hours, so most of my fresco will be pre-finished. I'll demonstrate how to apply a giornata on an unfinished bit (something interesting like a face or an angel wing). I'll mix the lime and show how to dovetail the previous giornata in order to fit the new section. After I paint on the wet plaster, I'll do some secco work to hide giornata divisions that may stand out, or other decorative embelishments. Egg tempura will probably be the best, as ilia suggested.( I know a cool secco technique using milk... let me know if you want to hear about it later... I've already digressed too much from panel painting....)

So... panel techniques. Again my experience is limited so bear with me. Gary, what your talking about sounds pretty involved and heavy duty. I don't know about hyrib metal laith, stainless steel aircraft cable, or copper ferrules, so it's hard for me to completely understand your process. I'm not going larger than 30x40" for this demo.... what size are your panels? Is it simply more durable for shipment, longevity, etc.? It sounds like you and ilia do this alot and it is very practical for you.
Also, the conservationists who taught me in Florence and the restoration supply companies (PHASE,and Zecchi) told me that cement and fresco do not agree. Humidity carries salt deposits through the cement too large to pass through the intonaco. The salt remains and destroys the matrix of the fresco from the inside, causing the surface to flake, fade and/or discolor.
I know these are panels, and natural moisture may not apply here, but does the wetness in the cement, arrechio, or intonaco ever affect your process?

Nathan