MAD ELECTRICAL?

The advantage of this is potentially better connections for the power when starting or running on the battery. amp-ga27-jpg.jpg

But the disadvantage of this arrangement is power flows a longer distance and through two fusible links, which are by definition smaller wires.
MADB-running.jpg

Better to run the vehicle from a direct feed from the alternator as illustrated below.
MADB-revised-direct.jpg
Fusible links still protect equipment downstream from the battery.
When the engine is running, the alternator will recharge the battery through the wire marked Charging.
Everything else that's attached to the main junction gets power direct with just one splice.

During start, power will flow from the battery to the main junction through the path of least resistance - or some proportion of each if the resistances are similar.