Quote Originally Posted by alexverzosa View Post
Yes, the batteries are in parallel during jump start (+ to + and - to -). The series connection refers to the connection of the starter(load) and battery(source).

While this is the case, I am not certain if this is why some call this a series connection. Maybe nakasanayan na lang din.

Regarding jump start procedure, wouldn't it be safer to connect negative first? I believe the body is connected to ground(negative terminal of battery). If one were to connect the positive terminals first and somehow touch both car bodies without insulation the person would complete the circuit, possibly causing the current to pass through the person. As opposed to when we connect negative to negative first, where there is very little chance of accidentally connecting the positive terminals because of the relatively lesser exposed metal connected to them. Of course, this is based purely on electrical theory and I'm very open to correction. Wisest would be to follow what is stated in the user manual of your vehicle.

As for jumper cable current rating, I'd go for at least double what your starter is rated.
Correct.
During jumpstart, you are not connecting two batteries but a load so you can not say it is "parallel".