I surmise this is more than likely a troll, but nevertheless;

Whilst it's most common for the majority of people to fly more than competently using thumbs only, and which is certainly the more natural whilst simultaneously supporting the transmitter with the hands, that's plainly just a nonsense which belongs in the same bin as the "can't fly mode 2 without inducing PIOs or inducing cross control interference" and other mindlessly repropogated mythology. Find a good instructor. How the stud wants to learn to manipulate the control inputs is up to him. Whilst the two conventionally accepted methods are thumbs or fingers and thumbs, he, or she, could use his toes for all I care as long as he could demonsttrate to me that he could do so (a) safely and (b) competently.