The submission has received one short comment and two reviews. The authors have responded to the short comment and the first review, however, the second reviewer raises some serious issues which need to be addressed. The revision should follow the suggestions of reviewers and the author's response, but it is important to also address the final suggestions of reviewer #2, especially in terms of the method used for results evaluation.

Although the paper presents a novel, potentially valuable idea
that could make selection of parameters easier for inexperienced
users (or users with expertise outside the specific application)
the selected case study is not very convincing and the overall design
of the experiment has some flaws highlighted by the reviewers.
The authors have addressed some of the reviewers concerns by
reformulating the statements made in the paper and by referring
the most critical concerns to future research.
This is an indication that the work is not quite finished yet and
the publication may be premature.
However, our special issue aims to demonstrate the broad range of topics
and research that is being done within geomorphometry domain and the submitted
manuscript fits well this focus and may generate a new direction of research.
The proposed approach will become increasingly feasible as the trend towards open science makes the data and software used in the published articles available and the
case studies can be designed in more rigorous way.
Taking this into account, I recommend to accept the paper after
additional minor revisions.
The needed revisions are described below - they are mostly issues where the reviewers comments were misunderstood and not addressed adequately and where new issues arose.

The revised manuscript now states clearly that when the DEM used in the case study
was not available the authors used SRTM or ASTER DEM instead.
It is important to show this in the Table 3 by including the resolution of the original DEM
used in the articles (e.g. in the brackets along with the CA threshold) where this information
is available.

Several comments were misunderstood:
Throughout the article the term "relieve" is not used in the right context ( please see
http://www.dictionary.com/browse/relieve?s=t )
leading to misunderstandings. Perhaps you wanted to say
reduce, minimize or eliminate?

Another case of misleading terminology is "magnitude of cell size" noted by two reviewers.
The sentence where it is used
"The difference in magnitude of cell size can better reflect the level of similarity between DTA 26 applications than the numerical difference in cell size. "
really does not make much sense. Perhaps you wanted to say that you used
"absolute value of the difference in cell size" ?

One of the reviewers suggested that the title is too complex, however,
in the revised paper the authors made it even longer and more complex -
shorter title would be desirable.