[Nervey]

...same electrical potential as the spot the battery negative already goes.

I believe It matters in rush current and the resistance involved as the current increases. He established a direct path to the negative terminal, which in-turn has a direct strap path to the starter. Because he grounded to the chassis is just "whatever", but jumpstarting with battery packs is much easier this way. Simply using chassis ground does not always provide the best continuity, especially as the current increases.

How I know without the explanation? Because there are times I could not jump start my truck with a battery pack using the chassis ground, but direct connection was fine. I want to video this so I can post it, but I (thankfully) haven't had a dead battery recently.

 

[Nervey]

^Yup. And because Honda put a 10 cent (that costs you $5) bolt in a fender is to pacify those of us who have complained that the engine hanger is too far away for jumper packs to stretch... and to add, fails on the engine hanger because it is painted, and just purely a poor answer to the problem. Yes, for a true, flat-out fact, Honda engineers can be cheap and not provide a solution but offer only an alternative. Regardless of the argument, the fender is a poor reliability point for jumping that needs instant rush current. Fine enough to "charge" over time, but not fine enough for quick demand. Make the hack of extending the ground terminal or live with the bolt are the choices. Honda doesn't care, it is a battery, they hope you just call roadside assistance.

 

[Nervey]

Probably not so much the engineers being cheap, but rather forced to work with a very tight budget.

Very true, and probably better said, thanks. I'm sure someone said, what can we do for no money to provide jump packs with an ability to connect without spanning to the hanger. I bet you're right.