Too bad that the translation dont work better!
"corrugated iron" means washboards
It is not just the independent suspension i guess. The AHC suspension is hydraulic/oil based - and had allows us often a good pace - often a bit quicker than the locals - without to bring less comfort.
There are severall levels of washboards - some of them we was able to ride - like it is just a normal road. On bad washboard only speed helps. When it was really bad 100 km/h it feels ok - or to keep below 15 km/h. Often the road has hidden jumps - and we had some flights with our travelweight of near 4 tons - not so funny - and so there are some kilometers we just drove also below 15km/h - but not many.
Therefore we spend many days driving slowly through national parks and watching animals - our real overall travelspeed was much higher than 65 km/h i think.
But back to your other questions
I did some offroad trips in Laos and northern Thailand - and never has to use spare tyre. When you see our weight near 4to - would you really add a 2nd spare tyre? It adds 65kg to the bill. An additional kaymar rear tyre holder also 70kg. I had a tyre repairkit with me - and had 4 tyres at home in switzerland. Therefore i cant buy this size in africa - i would had used DHL so flight in the tyres if necessary. And you can repair also mostly, and don’t have to take a new one.
Too our car is fully loaded well balanced, near 50:50 - which is perfect.
When you read everything you had read – we have killed a tyre – but we get em repaired with a tube later. Shure – without spare tyre – you start driving carefully till restocked / repair.
I`m not a mechanic. To change a tyre or replace a fuelfiltre is a challenge for me. So I don’t have to take spares with me – i`m not able to repair the car – also if I had them with me. And I had the experience in my other travels – that the local mechanics are able to fix most of the problems – and also be able to optain spare stuff. Think on our windscreen – we kills two of them. Toyota couldn’t repair it, they need 45 days for flight a new one in.
But the “grey” marked had cheap Taiwan copys of windscreens – and after 3 hours we was able to travel again.
And also when you can do a lot of mechanic stuff by yourself – your car will break when you add to much weight with spares.
Yes we got stuck. But I like that - it was much fun to winch us out of the mud.
We had 33” tyres, bigger than the local ones, had 3 difflocks, mud terrain tyres and with 285 less small tyres compared that what locals use. Equipped like that – you can handle near everything, also with 4to. We often was near to get stuck – but mostly able to get throught at the last second.
I don’t had a chance to use our ground anchor (because palms was strong enough) – and as we stuck in sand we dig us out without the maxtrax – because it was more work to get them from the roof than to dig a bit.
There was some stuff who scares us.. As we entered Congo (leaving Cameroon) we does it on some unknown really bad tracks – and a thunderstorm cames up, with heavy rain. The back of the car try to lead the way – and we drift over a long way over 2 hours. It was much fun to drive, but pretty dangerous to smash the car…. I was wet from sweating. And we also had could stay till the rain stops, and the tracks get better. Fun and dangerous stuff are mostly nearby.
Also scars us the evening, where we got discovered by the mauretan military – in the night they looked similar to bad guys, when you see a pickup with armed guys behind.
And when your car dive – the half of your windscreen is covered with water – fu… yes we was scared, also with a snorkel.
Therefore we had a fridge and a freezer – we always had good food, that’s right. But we like to do wildcamping and to cook by ourself, and to scout a good place you need daylight. Near a big village (this may have somethimes something like a restaurant) – you cant setup a hidden camp. We just got 3 times discovery by locals, what shows that we mostly did a good job
We aren’t afraid about locals – but at the evening we want to cook, eat and relax – and don’t like to be the sensation. Mostly we had no language to talk together, because no one could speak english, so there everytime a bunch of people around you – that talk – and you don’t understand them.
So it was all over – very relaxed. Sometimes there are people who wants a bribe – but with some time we was able to avoid that stuff.
Our baddest experience was in Marocco with the corrupt police officers. But there we paid the normal finet with receipt/bill – and don’t feed his pocket with the half of the amount. And bad was some border crossings, but that stuff you know before you start.
We often drive through checkpoints where the police guys try to stop us. They wave us to stop – we wave back and keep driving and smile. This saved us a lot of time. They are nice – but the discussion was mostly wasted time – they just want to chat and get a souvenir. Just two times this behavior cause some angry – once in Angola we drove on the way back – 6 hours later – and meet the same checkpoint again – they remember ^^
And in Benin they want to fine us because of driving through – but a blond girlfriend with blue eyes – can calm them down easily.
I think 40% of the checkpoints who they want to stop us – we pass with waving back.
Only in Cameroon and Congo they use nail boards on the bigger roads to stop the people – there we stop every time
This happens on the big roads – on the small dirttracks they often seat near the street – and we passed them before they can react.
This worked well in Laos and northern Thailand too. But you have to look how you do it. Sometimes when they signed it very cleary – and you cant do like “I don’t see, i`m dreaming and stupid” – please stop
It depends on the situation. Also when they wear more than pistols – don’t drive through!
While wildcamping we don’t feel too save. Mostly we put every stuff inside of the car – to avoid that we miss something in the morning – and to be able to start quickly if necessary.
We had also planned to be ready for “quick alert starts” – but forget that. When, then someone will knock on the door with a gun – and you better stay.
The local people where everywhere very nice and helpful – also when you try to communicate with hands and feets, and they try severall times to help –and try send us to better roads – meaning that we don’t will pass through because of the bad road condition.
But we was able to sign them, that we like that kind of stuff, we wondering if they had checked later – if they can help us out (and earn some money).
When do you was there? 
Many police guys on road blocks had no papers - and they proceed without showing any papers.
