It really surprises me that people fail to register the simple fact that the best way to not lose athletic ability is not to lengthen. Period. However, since this seems to be a circular argument (doubtful that this will stop it, but I'll attempt it at any rate), here goes:
Athletes of any kind, from recreational children's teams to professional players that have hundred million dollar contracts do everything in their power to NOT get hurt. At the highest levels, athletes get taken out of games and put on injured reserves for small sprains. Larger injuries, and you're out for 4-6 weeks. Ligament tear, you're looking at a year out.
With CLL, you're breaking - re-read that for emphasis please - breaking, both legs, skewing not only your biomechanical ratio (yes, if you lengthen all 4 segments, you can offset this some, but not completely, as you also throw off overall body proportions as well as your natural equilibrium and center of gravity), stretching soft tissue beyond its normal biological capabilities, reducing your range of motion in at least your lower extremities. In terms of total recovery, you're setting yourself back by at least 1.5 years. That is best case scenario, with zero complications.
Let's assume you hit best case scenario with zero complications. You've lost 1.5 years of practice, muscle endurance, aerobic/anaerobic capacity, motor reflex, hand/eye coordination, strength, power, etc. I could go on and on.
Take a simple sport like running. Let's say you're a recreational runner, and you're running a 9 minute mile over an average of 5 miles. If you stop running for 2 months, you will not be able to run those times. Full stop. You'll have to re-train just to get back to that level. Now let's say you undergo CLL, you are lucky and hit best-case scenario in terms of recovery, but you've stretched ligaments, muscles, nerves beyond their natural biological capabilities as related to your particular, unique body, you've offset your equilibrium, center of gravity and biomechanical ratios, and you've aged 1.5 years. Do you reasonably think you'll be able to run the same times as before? Do you think you'll ever be able to improve upon those times? Answer is no.
This is not a hard calculation to make. Just apply some simple logic and you'll get to the same results. This is not knee surgery to repair a torn meniscus or ligament. This is a complicated surgery where serious tradeoffs are made, with diminished athletic ability being one. I won't judge you for opting in. I participate in several sports, two competitively, one at a fairly high level. I have a good starting height - not 6', but not 5'4", and I believe everyone deserves to be happy, and if this makes you happy, regardless of your starting height, do the surgery. It's why I'm doing it. I'm prepared to hang up both sports - I do them for fun anyway - recover as well as I can, and just be content with being physically fit and in good shape for the rest of my life.
Let's face it, most people are recreational athletes anyway. No serious professional athlete would ever consider this. It would mean a loss of their career, instantly.
So don't expect the surgery to produce both additional height and to get you back to where you were athletically. It just isn't possible. Multiple Drs. have confirmed this. So does common sense and logic. Yet this question repeatedly comes up. Regardless of how bad you want both things, you can't have them. So reason and think this through and see whether CLL is for you, and what you are willing to give up in return for 3 inches in height. Read through diaries of patients who didn't have a stellar outcome - there are plenty here. The best case scenario generally only happens only under the best of physicians, the best of care, and lots and lots of preparation. All of which cost time and in the case of this procedure, a lot of money. And with that, your best case outcome is good consolidation with no complications, physical recovery after 1.5 years or so, a normal walking gait, and return to activity - but that's it.
And last - if your athletic performance is really that important to you, stay healthy, avoid injury, train smart, and always do your best to stay away from the surgeon's knife, whether it's this, or any other surgery.