This block is a hack, a not so elegant solution, to situations where you need to put pnForms plugins inside conditional smarty tags like if-then-else and foreach. You can get into problems if you make templates like this:
<!--[foreach from=... item=...]-->
<!--[pnformtextinput ...]-->
<!--[pnformbutton ...]-->
<!--[/foreach]-->
This is because the number of plugins on the page may change from one page to another due to changing conditions or amount of items in the foreach loop: on the first page you might have 5 iterations, whereas on postback you suddenly have 6. What should then be done to the missing (or excess) persisted plugin data on postback? The answer is: pnForms cannot handle this - your code will break!
So you need to tell pnForms that the block inside the foreach tags is volatile - pnForms should not try to save the state of the plugins inside the foreach loop. This is done with the volatile block:
<!--[pnformvolatile]-->
<!--[foreach from=... item=...]-->
<!--[pnformtextinput ...]-->
<!--[pnformbutton ...]-->
<!--[/foreach]-->
<!--[/pnformvolatile]-->
This disables the ability to persist data in the pnForms plugins, but does save you from trouble in some situations.
You don't need the volatile block if you can guarantee that the number of elements will be the same always.
