When it comes to studies that involve measuring telomeres as a result, I've always wondered: is telomere length such a foolproof measure that it can be used to

When it comes to studies that involve measuring telomeres as a result, I've always wondered: is telomere length such a foolproof measure that it can be used to make claims like this? Given two people who will live their entire natural lifespan and have no complications, will the one with shorter telomeres necessarily die first? Are there tolerances of some kind?