John, the spider web cracking is commonly referred to as "crazing" and juice coming in contact with the lid IS NOT necessary for the lid to craze. I have a 10 gallon BVV pot with Acrylic lid and crazing commenced on that one along about the second time I used it. It had nothing anywhere near the lid, I had several glad lunchmeat dishes in the bottom of a 10 gallon pot, stabilizing pen blanks. The fumes are enough to cause the problem with the acrylic lid crazing. That being said however, it has yet to implode, and still seals amazingly well several years later, however the acrylic lid on the 10 gallon pot exceeds 1" thick.
Like you, if/when it ever implodes, I'll replumb through the side of the tank, and replace with a glass lid.
