Can a Gm throw a spiral?
anyone can be a super GM

Can a Gm throw a spiral?
Depends on the GM. Being a GM doesn't have to preclude having athletic ability.

If you want to see whether you can improve in chess, try completing more games than posts.
I do, and I still suck. Good night.

"Anyone can do it if you just try hard enough" is a nice fairytale to tell to schoolchildren, but it's unfortunately not true. The world is full of examples of people who try and try and try and never make a real success of something.
This is particularly true when you're talking about a competitive endeavour. The problem with becoming a super GM is that you don't just have to reach an objective level of ability - you have to beat other people to do it, and rely on them not putting as much effort into it as you. It's like saying anyone could be an Olympic gold medal 100m sprinter if they tried hard enough - they just can't, because only one person every four years can do it, and you have a very limited amount of time in which to achieve it.
Barring some kind of real impediment, by trying hard you can often at least get pretty darned good at anything, but to reach the very top of any field effort just isn't enough - you need to have some degree of talent and natural aptitude, not least the stomach for dedicating that much of your life to studying chess to the exclusion of a lot of other things.
Well put!

Another idea,
Since some people here is saying that being an slower learner doesn´t mean that you can´t go to the top, and understanding talent as being a fast learner (even when I´m not sure if that´s a correct way to define it):
In order to simplify let´s say that there are two class of people:
Class A (with talent): They learn chess at "speed 100"
Class B (without talent): They learn chess at "speed 50"
Both classes start learning chess when they are 10 years old and study 7 hours per day during his whole life, who is going to be at the top and be the super gms?
Class A of course.
It doesn´t matter how much they trie, Class B can never catch Class A, even if Class A stop improving at let say age 45, life is not long enough for class B to catch up.

Natural talent is the best explanation for Morphy, Capablanca, Reshevsky, Fischer, and Carlsen. Work is important too, but without natural talent you won't be a super grandmaster.
Another idea,
Since some people here is saying that being an slower learner doesn´t mean that you can´t go to the top, and understanding talent as being a fast learner (even when I´m not sure if that´s a correct way to define it):
In order to simplify let´s say that there are two class of people:
Class A (with talent): They learn chess at "speed 100"
Class B (without talent): They learn chess at "speed 50"
Both classes start learning chess when they are 10 years old and study 7 hours per day during his whole life, who is going to be at the top and be the super gms?
Class A of course.
It doesn´t matter how much they trie, Class B can never catch Class A, even if Class A stop improving at let say age 45, life is not long enough for class B to catch up.
but lets say a is not that rigid and in reality he only learns chess for 5 hours a day and the other one learns at 10 hours a day..
Also you must take into account what there learning differences are after 5 years, the brain builds new connections (sorry i forgot the proper term).
So maybe the gap in learning speed becomes smaller. Well im not saying it is so, but unless someone educates me it could be a possibility.
Naw, two out of the three were just lazy.