If 10 cm has screwed proportions, it's likely 9 did as well. If 11 cm has screwed proportions, it's likely 10 did as well. If n+1 cm has screwed proportions, it's likely n did as well. See the faulty logic?
That being said, you are right about it being an individual-based thing. I did 8cm on femurs Precice and absolutely could have kept going if the machine allowed. As always, lengthen and observe. People shouldn't come in expecting that they can lengthen 12 cm, but I definitely think the vast majority of people can safely hit 8cm. 8 cm shouldn't be thought of as a "limit". It's more like the average safe amount that your typical patient can handle. Some can handle more, some can handle less.
Funny how that same 'logic' is always trotted out here no problem when someone is talking about
reducing their goals (i.e. no one's gonna notice 1cm extra in height bro!).
Yes it's true n+1 is likely only marginally worse than n in terms of proportions. I wasn't the one who brought up the proportions thing though, and you can just flip the same logic to a guy saying increasing a large amount will definitely ruin your proportions when it wont. Look at yourself in the mirror and decide if you like what you see is the only way to sensibly do this, but don't just stop at 8cm (unless Precise) unless that's genuinely your dream height or you look in the mirror and think increasing more in the femurs will look bad and outweigh the benefits of further height gain. But definitely don't decide based on 'the Lord our Father Paley said 8cm is the maximum', as Paley is just an orthopaedic surgeon, a very skilled one yes, but he's just a man, not a God, and is subject to the same biases and capability to be wrong on an individual case as anyone else. He's hardly going to tell prospective customers 10cm is safe for many when his nails only go to 8cm now, is he? They'd be on the next flight to Europe in that case.
Just out of curiosity, does the actual result is the same as the mockups? I mean does it look the same or actually better/worse?
I never did a 8.5cm mockup. I did an 8cm one in paint before starting the lengthening as at the time I also thought of 8cm as the goal. I'm not sure if it looks exactly the same as the mockup although 0.5cm isn't going to make or break anything in this regard. I think it looks perfectly fine tbh, like I say you can definitely notice the femurs are big but that's going to apply to anyone lengthening over 5cm or so.
Of course all this only applies when you're not wearing clothes. If you're in pants then it's completely indistinguishable from the rest of the population. And I've never had any comments even when nked, although I guess a girl is unlikely to say something like that to your face even if she's thinking it.
As for the height result being the same, yes I got 8.5cm increase in 'real' height, exactly as the xrays predicted once accounting for the discrepancy between my legs and the Q angle.