I have the custom profiles set for each of my wires, but yes Mactavish kind of sees what I'm saying. I enter the new number and it sets that number for all the wires. If it doesn't make a difference with setting the approximate tcr under the action tab for each individual wire setting, then no worries. Not sure if it did fine tune each wire to work more efficiently or not. I just used titanium as an example. My concern really is setting the approximate tcr value for reactor wire.