I have studied the table and worked it out as follows: 1st column is for honing results, 2nd column is for cutting speed in relation to grit size, 3rd column is for wear of the stone itself, 4th column is his overall judgement of the stone.
The numerals in the 1st 3 colums are: 1 for excellent and 6 for very poor.
The 4th column works with pluses, I presume ++++ is excellent an + is not so good.