There IS a limitation written in the standard. The FCI breed standard (
http://www.fci.be/uploaded_files/332GB99_en.doc) describe Czechoslovakian Wolfdogs as dogs with "above average size". Not "small" and not "huge" - but above average size. As "average size" FCI list breeds where males are about 65cm high. All breeds growing over 70cm are described as HUGE breeds.
So according to the FCI the Czechoslovakian Wolfdog male should have 65-70cm. Females should be smaller and easy to recognize (+ "Sex should be unmistakable.")
But here we do not speak about standard but about outcrossings. It is typical that outcrosses lead to high dogs. And the mixes with Saarloos proved this - even if the parents were small the puppies were very high dogs. The Crying Wolf kennel was known for years for dogs which hardly reach the minimum size. Now we have mystery litters where dogs grow bigger even than the Czech lines.
The same is visible in France where out of parent of average and above the average size we get dogs (where it is known that they are AWD-crosses) which reach much more that 70cm at early age.
The size is not the only proof but can be another advice that something is really going on in the mentioned lines.
my dod 73 cm, it's not a Clt fot Admi, to big? watt a pitty