I must admit I find this quite reckless advice.
If the car in front of you is driving a perfectly normal line through the esses, it is already leaving a gap wide enough for you to stick your nose in. But just because you can doesn't give you a right to do so. At best you'll simply annoy and slow down the driver in front. At worst - and very likely - you'll hit him, causing him to spin out.
Even if you're faster and the driver in front is making big mistakes in the esses, there's at best a one in a million chance of pulling off a clean pass unless he leaves the track on his own. It just doesn't happen.
I may done it to
you during a Suzuka race a while back, you may have been using a Ford GT at the time or similarly powerful vehicle with little downforce whereas I always use a light but low powered vehicle utilising masses of downforce where possible. One in a million and when I've attempted to make the pass it's only ever failed when the person I'm trying to overtake tries to come down on top of me when I'm already along side halfway to the apex. Any good drive knows when to back down from such a move, I always give room if I'm going to hit there rear quarter, but if im at there door they should really be checking their mirrors and I have every right to be there.
It is risky if you don't know what you're doing, or if the driver infront isn't paying attention, but it's not my fault if I'm already alongside and they try to come down on top of me. It's no more dangerous then late braking up the inside of one and blocking the racing line when alongside the other driver. You might as well just say every overtake is dangerous that doesn't involved just passing someone in a straight line.
Skip to :50, this is it being perfectly executed, going up the inside and blocking the racing line, now are you saying this is a dangerous move? The AI knew to give up the position, a human player may attempt to hang on around the outside and rightly so, but it's a perfectly viable. When I start to consistently hit people off when I try this move, I'll stop doing it, but I can hand on my heart say that I've never just punted someones rear half of the car and have only made contact when someone just doesn't accept that I have the inside line.
I've also only ever generally used it on GTP_ drivers who ones which I've seen to be clean and fair because of the lack of curtosy that a random driver may have and they may just come down on top of me. Have you ever ran 2 cars wide down the esses? because I've seen it happen and been part of it, so long as the drivers are aware and of similar pace you can go through almost the entire set of turns side-by-side.
The beauty of this overtake is the surprise factor, but I suggest those considering it to practice against the AI first. The cut-off between dangerous and safe is how far alongside you get out of the first turn and into the second, it requires taking a different line completely which I'll even draw out for you.
It's crude but bare with me.
Key:
Red - Normal (ish) racing line
Green - Path which the car behind takes to get onto the inside of the next turn (will automatically be carrying more speed into the turn in order to pull alongside by taking this line at the limits of friction)
Yellow - Shows the path the defending car should take if the green car gets up to the door of the 'yellow' car.
I think the original point was about sticking your nose up the inside... which is a lot different to having a significant speed advantage.
Not literally just shoving your nose in, how stupid do you think I am, I just meant getting your nose up the inside and the natural speed advantage of the different line will take you up to a door usually and the car on the outside should give way to some degree. If you (the overtaker) doesn't get alongside then you leave room, simple.
It requires good race craft and practice but it is by no means impossible and it's very easy to avoid an accident if an attempt fails, you're all capable of making such a move stick, or giving way when you can't. It's just as difficult as late braking into turn one and diving up the inside.