Oh, the supreme ridiculousness in the logic behind some of the multi-blade cartridges. Hindsight might seem twenty/twenty, but at the time the five blade razor was launched, it occurred so under much previous and existing ridicule for the idea.
What is now commonplace, then was considered ridiculous. First, there was the article The Onion did over a decade ago (even before the Gillette Fusion was released).
Then, there was the MADtv parody, showcasing the ridiculousness of adding quality to the shave by simply adding blades:
This particular video is reminiscent of and a likely direct spoof and satire of one of the vintage Gillette shaving videos from years past (at about the 40 second mark you will see it):
Truly, adding more blades does not necessarily equate to greater shaving comfort or a closer shave. We obviously reached the point where adding more blades became the proverbial point where marginal cost equals marginal benefit. Hence, we have somewhat of a return to the traditional wet shaving where the single blade of a straight razor or safety razor rules the day.
When it comes to your shave, don’t expect your shave to improve even more than marginally if you simply add multiple blades and use a cartridge razor.