Whenever I reply to a thread in here, I'm conscious that my posts on a second read the following day can sometimes appear a bit "rightious". If that happens here, please accept my apologiy. I am trying to put an alternative point of view, and NOT saying it is necessarily better than the one with which I am comparing.
#1 Nemesis wrote:
1) I was following a van at about 55/60 just before reaching this section [....]In front of the van I noticed a car on our side of the road, overtaking and heading towards us. There was a sort of double-take moment as I realised what was happening and how bloody close he was - he was shifting!! At the point I realised this I noticed the van in front brake sharply and of course I did too - slammed on very hard, (but not so as to skid). The van stopped dead, I stopped behind him (thankfully I keep good stopping distances), and the overtaking car just missed the van as he pulled in, and was not completely back on his side of the road as he passed me. I'm also very grateful I was not being tailgated. [...]

I guess the only thing that you might have been able to do differently on this one would have been to brake fractionally earler on "autopilot" - sort of "preaction" to what the van you were following inevitably was going to do. Also worth looking out for an off-road escape lane if possible - to avoid the van coming at you backwards if, after it has stopped, the oncoming overtaker is certainly going to plough into it - or in the event of you being tailgated by something big and heavy not reacting in time to the situation.
#2 Nemisis wrote:
[...] I was travelling at about 70 - clear straight highly visible section of road. I notice I'm rapidly approaching a much slower car (I hazard a guess he was doing somewhere between 40-45). Not a problem - road was clear, I had my momentum up, high speed differential and should be able to overtake swiftly and safely. However, as I started to pull out and overtake, my speed differential dropped. I hadn't slowed; it would appear the overtakee decided to accelerate. I was however, just getting past when two cars appeared round the rapidly approaching bend. Snap decision - I floored it and managed to get back in, though not without pushing my car's cornering capabilities to the limit. And causing the oncoming cars to slow considerably with headlights flashing at me.
What sort of car do you have, and are you in any way relying on the slipstream to slingshot you past things? I ask because if your car is generally low power, it is surprising how quickly speed can drop off when you pull out of traffic into an open lane.
Despite some aggressive "being overtaken" reactions reported in other threads, I still maintain that it's best that the vehicle being or about to be passed is aware of the situation if possible - I nearly always give a headlight flash or a quick pip on the horn as I pull out.
The odd time this has happened to me, I've mede the decision (and very occasionally changed it, requiring dramatic power or braking) as soon as I realise the differential speed has dropped off. Typically this is noticible before other cars coming the other way come into view - if not I suggest some "preaction" - either aborting or gunning it should be the reply to a loss of differential speed - before signs of any oncoming traffic.
#3 Nemesis wrote:
[...] stuck behind a slow moving HGV, van and car. HGV was doing between 35 & 40. However the van and car were both tailgating the HGV and showing no interest in overtaking.
Are you sure you're not mistaking "no interest in overtaking" for "very interested, but such a lousy driver so as to be too close and therefore unable to overtake"?
#3 Nemesis wrote:
I decided to hold back and wait for a good overtaking chance. Sure enough, one arose - I followed my usual procedure - ie drop back, accelerate on my side of road, and then ensure it's still clear before pulling out.
The problem with accelerating and then pulling out is two-fold: a) The chances are that the van and likely the HGV were unaware of your intentions until they were well underway. b) Temporarily at least, you are restricting your own view of what's happening in front of the lorry - including what might be coming toward you around the bend at the end of the straight. I say better to pull out early to overcome both of these - you still have the option of getting back in and braking - you're not committed until you're level or almost level with the first car.
#3 Nemesis wrote:
I was going rapidly past the car that was directly in front of me, when for some reason the van driver decided to pull out and barely accelerate!!
This is classic. He likely realised that an opportunity had arisen as he was on a straight, and was reassured to some degree having (possibly) seen you on the wrong side of the road, therefore realised he could cautiously come out, when he then saw/thought it was clear enough for him, so stuck his foot down. All dramatically wrong, but sadly, sufficiently common to be one to watch out for. I can't recall any "trebles" I've done in recent years on single carriageway roads, probably for this very reason.
#3 Nemesis wrote:
Quick reactions stopped me running into the back of him, but he was barely going past the HGV - he got halfway along it when oncoming cars appeared. So he braked and pulled back in behind the HGV, and I'm stuck next to the car having lost all momentum with cars approaching. All I could do was brake and pull back into my original spot behind the car, [..]
The odd time I've had an overtaker pull out in front of me while I've been overtaking, I've *always* got back over, into whatever gap I could find. In this case, I'd have had the same gap as you - but I think/hope long before the van aborted his manoeuvre. Once he's out, you're effectively unsighted and the only safe place is back on your own side of the road. I've missed many an opportunity of overtaking by getting bacxk in - and saved being hung out a few times.
Nemesis wrote:
All three of these incidents could have resulted in very nasty, potentially fatal crashes. But not one of them would have been caused by speeding [...]
Given such a concentration of close calls in the same location, I can't help wondering if there is something deceptive about this location - perhaps trees or similar make the straight tlook a lot longer than it actually is?