Even if 16.4 volts might be safe for electronics still attached to the battery, I don't want some charger blasting past 14.5 volts and putting out its maximum power until the battery gets to 16.4v Like My Schumacher does, Sometimes, whenever it decides to, randomly.
Not on any battery I care about anyway.
Other times it flashes the green light and gives up when the battery still requires 5 amps to be held at 13.2v.
A single battery accepting 5 amps at 13.2v is anything but fully charged.
But the 'just fine, green light brigade' only need to see a green light, to declare it is just fine and to 'follow me over the cliff!'
Shame when they give advice.
Bigger shame when others take it.