This is what I think is the most realistic classification of male height ranges and looks level. All heights are barefoot afternoon heights measured under stadiometer without socks and with buzz cut (i.e. real heights) so keep that in mind:
1. 5'5-5'8. This is the lowest height range where a male can fall. Below strong 5'5 is no longer considered normal male height and is not salvageable with any looks level one can imagine. At this height range one is capped at so-called "chadlet" looks level, i.e. if one is very good looking and hot, he is limited by his short height and can never become proper "chad" unless he does LL. Optimal chadlet height is average of 5'5 and 5'8 so it's about 5'6.5.
2. 5'9-6'0. This is the height range where a so called proper "chad" can be. Basically, at this point, you're no longer limited to your short height and you can get any women interested in you unless they're very tall and / or have strict height requirements of above 6 feet. While at chadlet height tier one is very limited due to his height, at proper chad height tier one escapes the height limitation and is no longer defined by his height. This is the most realistic height range where chadlets can end up with double LL. Basically, 5'5 chadlet is capped at 5'10.5 with 5.5 inch double LL whilst 5'8 chadlet can end up 6'1.5 if he maxes out at 5.5 inches with double LL. So, 5'5 guys have a hard limit of never going above 6 feet (unless they lengthen 8 inches which is unrealistic) whilst 5'8 guys can break that 6 feet barrier and become legit tall. Optimal chad height is average of 5'9 and 6'0 which is 5'10.5 (This is the height 5'5 guys can get with 5.5 inch double LL which is a decent height for a male).
3. 6'1-6'4. This is the so-called "gigachad" height range. Proper gigachad should be at least 6'1 which is tall. Above 6'4 is too tall and has no benefits socially. Optimal gigachad height is average of 6'1 and 6'4 which is 6'2.5. This is the height range where proper chad height males of 5'9-6'0 can and up with double LL. Basically, at this height range you're no longer limited by your height which means that you can get those height fetishist women who think that 5'9-6'0 is too short for them.
Now, getting double LL makes the most sense when you're in 5'5-5'8 range to escape the short height stigma and unlock your full potential by going from chadlet to chad status. While at chadlet height range the majority of women despise the idea of dating you (ONS and FWB doesn't count), at chad height range about 80-85% of women are okay dating you. This is the huge ROI you get with double LL and is the most beneficial of all starting heights. Basically, the lower chadlet height you have, the more you gain with double LL of at least 4.5 inches. It means that starting at lowest chadlet height of 5'5 you can end up at 5'9.5 with 4.5 inches of double LL (very realistic goal with 2 LL surgeries). It's literally the most beneficial jump out of any starting height.
Now, at 5'9 getting LL still makes sense to break that 6 feet barrier and enter in gigiachad tier height range but ROI is not as strong compared to someone who goes from chadlet height range to chad height range. While at chad height range you're capped at 85% of women who would date you, at gigachad height range you get access to those 15% of height fetishist women who strictly date men above 6 feet tall. It's still beneficial to do LL at 5'9-6'0 height range but the life quality improvement won't be as drastic as someone who goes from 5'5-5'8 range to 5'9-6'0 range.
This means that getting LL for strictly height boosting when one is above 6 feet tall is nonsense and the ROI is negligible.
As you can see, there's 11 inches of height between the 5'5 and 6'4 (lowest and upper height ranges of normal male heights). The ROI of getting LL is the strongest at 5'5 and gets lowest at 6 feet, where you're just an inch away of proper gigachad height.
Now, at 5'5, when you stand besides 6'4 guy, you're literally 11 inches shorter than him (brutal height difference). It's about 27-28 cm which is more than an average male head. If you do 5.5 inches of LL at 5'5, you're basically halving that height difference and now you're just 5.5 inches shorter than a 6'4 guy. To imagine the height difference of 11 and 5.5 inches, at 11 inches shorter, your head is about 3-4 cm lower of 6'4 guy's chin and at 5'5 inches shorter, your head is now just about an inch lower of 6'4 guy's eyeline, which is a huge difference. Basically, at 5'10.5 you're no longer a manlet by any definition of this word. It's a solid height and that's why it's the most beneficial in terms of ROI to go from 5'5 to 5'10.5 with 8 cm on femur and 5 or 6 cm on tibia.
To recap, at 5'5-5'8 range, you're limited to about 10-20% of women who would date you (10% at 5'5 and 20% at 5'
.
At 5'9-6'0 range, you're dating pool is about 70-85% (70% at 5'9 and 85% at 6 feet).
At 6'1-6'4 range, you're dating pool is practically at 90-100% (90% at 6'1 and 100% at 6'4).
Basically, a 5'5 guy's dating pool goes from 10% to 70% if he does 4 inches of double LL which is the highest gain of any starting height.
But, at 6 feet, your dating pool goes from 90% to 100% if you become 6'4, so just 10% increase, which is the lowest ROI you get from doing LL at 6 feet.
That's why they say it's a life changing surgery for 5'5-5'8 range guys. Anyone starting at 5'9 should rethink of getting this surgery done and once you're about 5'10.5, it approaches to the lowest ROI of getting it done.
Basically breaking that 6 feet barrier with double LL when you're 5'9, your dating pool goes from 70% to 90% which is still a worthwhile and boost and QoL improvement.
But, in terms of getting the most ROI, going from 5'5 to 5'9 or 5'10.5 where your dating pool goes from 10% to 70-75% is the most dramatic QoL you get from double LL.