The advantages of high consistency refining in tissue paper:

For treating hardwood pulp, the high consistency refining system can increase tensile and bursting strength so to lessen use of softwood fiber. 

It can soften the fiber by rubbing the fibers, and then improve the paper touching as a result. 

Bulk can be maintained while the tensile get raised by the fiber’s kink and curl.

Fiber retention can be increased which can reduce the consistency of white water and save fibers.