No, there additive alright but additive in a way that you can mismatch them into being different charges(the one applied to kritzkrieg can be turned into one that does what the one applied to quick-fix does):
PHP Code:
"medigun charge is crit boost"
{
"attribute_class" "set_charge_type"
"value" "1"
}
"medigun charge is megaheal"
{
"attribute_class" "set_charge_type"
"value" "2"
}
"medigun charge is resists"
{
"attribute_class" "set_charge_type"
"value" "3"
}
Looking at the above charges attributes, you can easily notice that A) they share the same attribute_class and B) follow a number ordering system.
so doing 18 with value of 2 does exactly like 231 with value of 2.
Doing 18 with value of 1 and 231 with value of 2 does exactly the same as 473 with value of 3