If LOG1() or LOG2() is only provided with a SINGLE argument, then Serial.print() is called. This allows you to continue using LOG1() and LOG2() to directly print any variable or object that is handled by Serial.print(), such as an int, double, or even an IPAddress.
If LOG1() or LOG2() is provided with multiple arguments, the first is considered the format and Serial.printf(format...) is called. This allows you to use printf-like functionality within LOG1() and LOG2().