The whole experiment is based on learning from other code samples (see http://www.cs.siue.edu/~astefik/papers/StefikPlateau2011.pdf). That's what they measured -- how easy is for the beginner to learn from the code samples.

If you don't explain the logic behind the special characters, of course it's easier to learn what the code is about from the notation which has less special characters and less semantic behind the special characters, like their better faring language:

  action z(integer a, integer b,
  integer c) returns number
  number d = 0.0
  number e = 0.0
  integer i = a
  repeat b - a times
  if i mod c = 0 then

I'd say the students were talented if they managed to make reasonable results in any language, from my perspective, their "better" language is still way too hard for absolute beginners.