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Comment by jplrssn | Hacker News Reader

I've never driven an EV but I'm curious about this statement. When would continuing to accelerate ever be the desired behaviour when pressing both pedals at the same time?

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In normal driving (EV or ICE), no.

There's some corner cases where using both can be beneficial (like heel-toe downshifts with manual gearboxes, or changing the way torque is steered on AWD), but they're generally pretty far removed from the way that driving is usually taught or performed.

Even the classic parking brake hill start in a manual car involves braking and applying engine torque at the same time, despite the fact that the brake pedal isn’t being pressed.

But starting on a hill in a conventional automatic with a torque converter also involves either rolling back a bit or pressing the accelerator a bit before releasing the brake.

>But starting on a hill in a conventional automatic with a torque converter also involves either rolling back a bit or pressing the accelerator a bit before releasing the brake.

Felt deeply in San Francisco. I think newer cars rollback less than older cars. Either way, it is unnerving when driving in Lombard street.

You can't pay me enough to drive in SFO in a stick shift.

Many modern stick shifts have "hill hold"[1] that keeps the car still until the clutch makes contact. Still, would need good throttle/clutch control not to stall after that.

[1] https://en.wikipedia.org/wiki/Hill-holder

I don't think it would be. I read parent post as "when pressed enough to trigger the switch, the brake pedal has priority and disables acceleration." There may be a tiny amount of pressure that you can put on the brake pedal before it detects the press.

It's handy to have brakes and acceleration when you want to spin the tires (2wd).

Sometimes necessary for tricky hill starts, I won't fully remove the brake until I feel the accelerator moving the car forward, but that should fit within the GP's 'little bit'. EVs should be easier on hill starts because there's potential for less latency between input and power delivery, but I dunno; I don't care for driving east across downtown Seattle regardless of if I'm in an all gas or a PHEV.

"Hill start" buttons have been standard on ICE cars for some time now.

Hell, my 1987 Toyota pickup had one. You could put it in 1st gear, let the clutch out and then turn the key to start, if you were on a very steep hill. Comes in handy offroad.

My 2017 Chrysler Pacifica doesn't have a hill start button (nor does it just do it, afaik, which I've had with some rentals), so I'm not so sure it's standard on ICE cars for some time.

My 2014 PHEV does have a button, but I don't use it, because when I'm in the situation that needs it, there's usually cars behind me, and that's not a good time to test and see how it works.

Fair enough. I should have used the word "common" instead of "standard."

Starting on a hill is the common case, for me anyway.

I also imagine that two-foot drivers would prefer for the effect of pressing the brake to be smooth, and having the slightest touch instantly reduce motor torque to zero could be jarring.

It can be pretty useful in offroading to hold a medium-high amount of throttle and use the brakes to modulate as they're more responsive, but it's hard to picture a cybertruck doing that kind of offroading. Not to mention it's only necessary due to the throttle/drivetrain response curve - that might be entirely negated if the low speed throttle response in the EV is decent enough for crawling.

It's the most straightforward way to get your brake lights to come on without actually slowing down.

I've done it a few times to make people following too closely back off of my rear bumper.

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