I don't want to derail but if the issue that turns people off is the all-or-nothing aspect, I suggest you test any or all of the steps separately. My humble two cents:
I haven't yet gotten Brewtan to test but I do see an improvement in lagering time from a) preboiling and using 60ppm smb in the mash water, and b) using pvpp in the whirlpool. My aim was to prevent the formation of polyphenols, or precipitate them, which aging usually does for me but gelatin does not. I still have a copper pick up tube and didn't keg until fermentation was 90% done, but I do push out of my stainless fermenter using CO2 into kegs purged by pushing out sanitizer.
I also noticed less darkening of the wort during boil. My kettle pH was 5.2, lower than normal 5.3-5.35, so I don't know how much is attributable to that. If I did more rigorous test I'd look at the color of first runnings.
So, there are multiple poasible benefits. For what I need, part of the process may be enough. That being said, a traditional long lagering period has done well in the past, though it may not give you the modern "big brewer" taste if that is what you want. I'm also excited to try Brewtan because I'd really like to avoid lengthening the brewday unless it's unavoidable.