Q. Which class runs total models processing?
Mage_SalesRule_Model_Validator::process() (applies and processes rules for each item of total models)
Basically, rules are sorted by the priority and Magento applies rule by rule for each item
Mage_SalesRule_Model_Validator::process() (applies and processes rules for each item of total models)
Basically, rules are sorted by the priority and Magento applies rule by rule for each item