true, to use ISO password hashing algorithm; otherwise, false.
The spreadsheet utilizes the ISO password hashing algorithm to calculate a strong password verifier that is used while protecting a document. MS Excel also utilizes this algorithm for protecting a document starting from MS Office Excel 2013.
The algorithm complexity depends on the SpreadsheetProtectionOptions.SpinCount value. By default, the SpinCount equals to 100 000 like in the MS Excel algorithm. To make the document protection faster, decrease the SpinCount value.