I wanted to get my silly ph thought process out there. The plants and bacteria can alter the ph for the own needs. So lets say you pour a lactobacillis concoction into your soil. Well those bacteria operate at low PH. Honestly not 4 ph low but pretty low.
There are also acid loving bacteria that live in the soil. Those bacteria live in ph as low as 2. maybe lower. Now im not saying those bacteria are present in your soil at all times, but lets say you have a severe ph problem. Lets say ph 6.4 for a couple days. Those bacteria will find(spore to) your soil and start to break down the metals, and if they become established in your soil they can create pockets of very low ph. Not only does this make aluminum more available but the bacteria that are in your soil is also breaking down the aluminum without the low ph. So in the long run azomite or other aluminum(or any toxic metal) containing amendments could build up and leach if you have the tiniest ph issue because now these bacteria are doing the dirty work, not the ph.
Call me crazy. It is OK lol
And I thought I would include this. You can continue googling or tell me i'm crazy. I might just listen lol
http://www.els.net/WileyCDA/ElsArticle/refId-a0000336.html