I just spent the last week or so printing the same high contrast 4X5 negative using graded paper (Oriental grade 3), and Adox VC with Dupont filters using single contrast, split grade, split grade with the Emmermann Process and the Emmermann process alone, and the Emmermann process printed dark and reduced. I don't have access to a scanner so I am unable to show the results, but did not find (my personal taste) any significant difference between printing on grade 3 paper, single contrast with #7 filter, or split grade using #1 and #9 filters. I did see a difference with the split method and the Emmermann process, but the highlights were a little too gray for my taste, but when printed dark and reduced showed quite well and I felt it made a marginal better print than the print made on the grade paper, although my wife likes the grade 3 print. I plan to print a round of test prints over the next week to see if another print makes a difference and see if I can find a copy of a book with more information on split grade printing.
Paul