The counting/calculation estimate is based on counting countable indexes such as stories, usage scenarios, marketing requirements, web pages, technical requirements, functions. Estimation by test cases as I understand based on counting test cases and categorizing them into groups such as easy, medium, hard. After these categories are created we assign average time to each category and multiply by the number of test cases. After that, we sum up the results.
If I understand everything correct, can estimation by test cases be included in the category of counting/calculation estimation? Because it looks like we just use test-case as an indexing value.
If we cannot include this estimation method into counting/calculation estimation category please explain why and explaining the differences between the two which have not been covered above.