No, no, that's not what thebimbo meant (see below)! To run through the thing from scratch:
Your charger plugs into your electricity supply with a household plug. Let's call that the Mains Plug.
At the other end of the charger you have a lead with a small 12v socket (usually white). Call that the 12v Socket.
Attached to your battery terminals you have a short lead with a 12v plug (usually white). Call that the 12v Plug.
All you need to do before you use the car is disconnect the 12v Plug from the 12V Socket.
Then take the charger and it's tangle of wires well away from the car, and put them somewhere safe. It's all too easy to run the damn things over if you leave them on the floor and you're in a hurry (I once managed to drive out of the garage without opening the door, but that's another story)!
There is NEVER any need to unbolt the short lead which is connected to the battery.
thebimbo was referring to the order in which you do these things.
When you're going to put the charger to work, FIRST connect up the 12v Socket and the 12v Plug, THEN plug in your Mains Plug and switch on the mains electricity.
When you're going to disconnect the charger and put it away, FIRST switch off the mains electricity and withdraw the Mains Plug. THEN disconnect the 12v Plug from the 12v Socket.
Where is the short lead which is connected to your battery? Presumably in the trunk of the GranSport, and presumably easily accessible?