A person more stressed has less mental capacity for everything else including pedestrians, why the heck do I have to explain this to adults? Stress leads to mistakes, every single time, in any activity. Whole sports and strategies are based solely on making competitor more stressed to induce mistakes and lose.

There's a sweet spot. "Eustress"

https://en.wikipedia.org/wiki/Eustress

And yet they're safer. All data so far seems to show that turbo roundabouts are very safe.

You might find https://news.ycombinator.com/newsguidelines.html an interesting read.

And there's ample research showing that drivers respond to low-stress designs by going faster and not paying as much attention to things on the periphery. https://grist.org/cities/heres-why-narrower-streets-are-safe... or the illustration at https://i.pinimg.com/originals/e2/e0/dd/e2e0dd89a67fe1df1e6d... are useful.

Would you be so kind as to explain to me your thinking to the contrary, ideally with sources?

There was a fad a couple of decades ago for "mini-roundabouts". They woud install these at junctions with a record of accidents. They were dirt-cheap, because they consisted of simply a couple of roundabout signs, and a circular bump about 6" high and a yard or so across, with smooth sides (i.e. no curb, you could easily drive straight over the bump).

The rationale for these things was that they induce uncertainty in the driver, prompting him to slow down, pay more attention, and look more carefully. There are other schemes that were intended to induce uncertainty. The problem with all these schemes is that they depend on unfamiliarity to work; once a particular mini-roundabout is familiar, it no longer induces uncertainty.

On the ring-road around my hometown, there is a series of "hamburger roundabouts". These are large, multilane roundabouts, with traffic-lights as well, and with a lane-pair that runs straight across the central circle, for through traffic. These configurations have never become at all familiar to me; they always induce uncertainty, and I hate them.

Those roundabouts are crap and people just drive over them. They're effectively unmarked 4 way stops, at least in Ireland.

If it's physically possible to drive over something, drivers will. A round concrete blob won't matter.

> And removing the possibility to change your mind in the roundabout reserves more mental capacity for looking for pedestrians

I don't buy it. Ending up forced to take an unexpected exit in a city triggers a lot of things for me and none of those are pedestrians:

- which lane should I be in for the quickest way back?

- what are the rules on the road I'm turning into? (this may be extremely not obvious if you didn't remember the sign for the road you weren't supposed to be on)

- does this road have restrictions that mean I actually can't be on it?

- is this going to send me on a toll road? (the joys of ending up on a single lane bridge which requires coins to cross and there's 5 cars already queued up behind you)

It's less of an issue for country roads, but being in the wrong lane in a place like this: https://maps.app.goo.gl/H8p1n8dcJ9D8epDG6 may mean you're doing a 30min detour to the same intersection and you'd better get it right this time!

Right, and when the junction design forces you to take the route you already decided on all of those decisions are moot. You are forced to decide _before_ you're mid-junction with people going all sorts of different directions. When you take the wrong offramp do you back up on to the freeway?

The toll road example is fair, though I don't know the particulars of this in Australia.

I recently drove from Normandy to Amsterdam and halfway through Belgium I took the wrong exit and ended up adding 20 minutes to the drive. But it was fine.