Actually important just in case on a battery discharge, but keeping an average close to stock car load request, not even that is really important.

The main problem has allways been the constant car load added by a constant battery discharge status due the stock low alt capacity at iddle. Once that is saved, you are maybe saving around. 10-15 amps of constant extra load running throught the charging system to recharge the batt when revving up the engine. If the car tipically demands 25-30 amps of load at night for example, this increases up to 35-45 amps. This is the red line to the bulkhead.