No Risk Option Strategy

There seems to be a few of these about.
Tree has some available for purchase and a few others who are option savvy have alluded to their existance.

I have a few questions.

(1) What would be the expected return in % terms for one of these trades on its completion,over what period of time?
(2) Other than the stratagy itself what else needs to be considered---can it fail due to lack of liquidity?
(3) Is the position sizing limiting---eg could I trade $100K or more using it?
(4) Time does the setup occur regularly---or is it as rare as hens teeth?
(5) Are we better off trading it on a more liquid bourse like the US? or DAX.

Finally is it/theyTRUELY RISK FREE

Hi tech/a,

I have yet to see any claim of 'risk-free' strategy that is not idiosyncratic, impracticable or just plain fuzzy math.

Idiosyncratic = dependent on Market conditions that do not readily occur or are necessarily repeatable.

Impracticable = requiring excessibly complicated or large capital outlays for minimal returns.

Fuzzy math = illogical or fringe-mentality strategies.

Each must decide whether they are hedging or speculating and IMHO better to develop trading skills that are 'risk-less' and put non-linear PROBABILITY of success in our favour ... my XJO system is an example: the purpose of which is to demonstrate it is possible and hopefully provide inspiration to others to work to develop their own systems.

Cheers ...