Rider instability

[Petrus]

A lót has been written on the MR2s steering, responsiveness, ´snap oversteer´ etcetera.

Don´t worry, not going to do a rehash 

Coming from motorcycles, racing those mainly and car racing/rallying as a less dangerous variety to do with my son;
having driven for work and fun hundreds of thousands om kms all over Europe;
having worked in emergency service;
I am acutely aware of the óther side of vehicle behavior:
The driver/rider.

I will throw in a generic statement to illustrate what I mean:
With racing motorcycles (and bicycles), less stable simply refers to a bike that reacts more twitchy to unwanted rider inputs in less than ideal surface conditions.

Let me clarify:
A single track vehicle is constructed inherently stable. This we can see on tv when a racer drops off his bike and that after some wobbles restores stability to continue perfectly straight.
Anyone who has even experienced a ´speed wobble´ on a bike knows this vééééry well.
It follows that rider/driver experience/competence is a vital factor in how the vehicle behaves because of the input given.

The less input a vehicle needs for directional change; the more important that input.

On a motorcycle/bicycle it is obvious that the handlebars often also support the rider´s weight and that unwanted input is véry hard to avoid.
On racing motorcycles a LÓT of effort goes into supporting the rider by other means. P.e. knees or chest.

Now we move to the car.
Same applies.
At léast as extreme because being a two track vehicle it has less/no inherent directional stability.
Basically áll directional change comes from driver input.

Now we move to mid engine concepts.
The crux for those is that they need less input for directional changes, change direction quicker.
See where this is going?
Right, enter our Spyder/Roadster.
This delightful little car is very light in the steering department. Changes direction swiftly, the driver input aided by electric power steering.

Now add the OEM seats not offering much side support.
I will now project it onto myself to avoid sensitive egos 
When cornering fást near the boundaries of tire adhesion, the centrifugal force pushes me to the outside. I really, réally need to brace myself. It is quite a challenge to keep this insulated from or compensated by my shoulders, arms, hands.
Add bumps and or ´roller-coaster´ surface, and I have a hard time not holding on to the steering wheel and giving unwanted steering imput.

Where I am going with this?
Nowhere!
I simply want to share that the car is only part of the equasion.
Additionally less so on track than on way less perfect real world public roads.
A perceived instability can very well be ... me.

[Petrus]

Having established that a huge part of what my car does is me, I bought seats giving more side support.
Very   
The car is more stable now.

Let me relativate.
The car drives as before obviously.
Going quick I now no longer need to brace myself, need no longer compensate for that to keep it form translating into steering input. Well, less, way less.

I have to a large extend eliminated my unwanted steering input.
To put it in other, an example in a bit exagerated words:
I have improved my car´s bump steering by eliminating myself 

[Carolyn]

Yes, just 'hanging on' does cause big inputs.

In my case, with a bad neck, just holding my head up in corners is a problem.

Hence:

[Petrus]

By Jove Carolyn, that is a cool, creative illustration of the issue; the centrifugal forces on the driver.

I wonder though.
With your head supported but your body not, do you not still tension the neck to keep the shoulders in check?
Maybe, because you are of slight frame that is less of an issue than for more bulky drivers.

[Carolyn]

I find, being skinny, that my PFL seats hold me quite well.

I now consciously relax my neck and let my head rock from side support to side support.  I also sit well back into the seat to make sure my head is back in the restraint.

Worst thing you can do (like on a bike) is tense up.

[Petrus]

I find, being skinny, that my PFL seats hold me quite well.

I get that,

I now consciously relax my neck and let my head rock from side support to side support.

That is the trick with supportive buckets too; just let it all hang out and relax, concentrating on steering.
Despite the positive feedback; being positively reinforced behavior, it takes getting used too.

Worst thing you can do (like on a bike) is tense up.

Exactly. It equals to translating all body movements into unwanted steering input ánd makes all wanted steering input a challenge.
It is a tricky one: The negative reinforcement of the behavior (the unsettling of the car) tends to aument it rather than discourage it.

[Zxrob]

Having rode for  many years on the road and done endless motorcycle track days, I can totally concur with the majority of your post, being comfortable, having the controls and environment correct for YOU is so important to your inputs and obviously outputs.

Rob