Wow. A shotgun experience!
For l/t storage one could puncture the lid with an icepick and then scotch tape over the hole. If pressure builds up too much, it'll break through the tape instead of breaking the jar.
I would suspect it's a volume issue. 10 bricks will outgas a lot and a gallon jar has plenty of space for that pressure to build up in. I had a single bar aging in a quart jar that I recently opened without that happening. Many people feel that there is some fermentation happening within the plug or brick itself. If true that would explain the pressurization. Multiply that by 10 and your results would seem reasonable. I think you could claim that aged tobacco to be a "Blast".