Hi again Richard and as I posted, the Comfort connector is designed to make the connection of a battery charger to a specific battery an easy chore.
I also posted, and this is based on my OPINION only but with the different ways modern vehicles now use the cranking battery’s negative terminal and/or cranking battery’s negative lead, it would be prudent to use a negative point away from the battery.
This will not effect the charging of the battery but it may prevent erroneous info being gathered by the vehicles BMS.
These two earth studs are just in front of the cranking battery compartment and are far easier to access so there is no need to touch the cranking battery’s negative terminal in the first place.
https://www.aulro.com/afvb/images/im...15/11/1084.jpg