Importing a document could result in a big UsedCellRange due to the big range of the imported DataValidationRule cell property. The UsedCellRange calculations should ignore this property. This could lead to a performance diminishment when exporting.
The feature is going to be included in the next official release Q1 2105.
Implement Protection feature.
The feature is available in Q3 2014.
The feature will be available in our official release 2015 Q2.