You can use this method to get parameters from filter conditions. I used it to get parametric fields to calculate…
You have lots of restrictions i know. You are at client side and you can nothing about business logic. But…
There is nice article for one reason https://community.dynamics.com/crm/b/crmbusiness/archive/2015/11/06/crm-2013-when-using-fetchxml-is-better-than-odata