4.2 was not all about bling, it also included a lot of bug fixes which were lost in 4.3, because...
4.3 WAS in fact based on 4.1.x.
In more length:
No they are not. In 4.2.x, xorgwizard creates a working xorg.conf file for my machine. In 4.3, it does not.It doesn't really matter if you use 4.1.x with pwidgets or any other (useless) addition from 4.2.x or simply 4.2.x, the result is same.
I know this intimately because I'm the one who fixed this in 4.2.x after putting up with it for years.
4.2.x was not all about bling. That is only the most visible difference for pretty obvious reasons. There were also a lot of fixes for a lot of problems. The insert bug. Xorgwizard. We made USB installs offer the user a chance to supply boot options each boot, like the CD does. We fixed/improved a number of things in the init script. Etc.
Bovine Digestive OutputAnd NO, 4.3.x is not built from 4.1 binaries
It most certainly is built from the 4.1.x binaries. Yes, he upgraded a number of things. But everything that wasn't upgraded or new came from 4.1.x. Just as how everything in 4.1.x that wasn't new or upgraded came from 4.0.x. He did not recompile Puppy from scratch or replace all the core stuff with packages from another distro. Sure, there are a lot of big changes between 4.3 and 4.1. But by no means so many that it would no longer be based on 4.1.
Woof vs. Unleashed makes no difference. Woof and Unleashed are just groups of scripts that are used to take a bunch of binary packages and combine them into an operating system. To use the 4.1.x packages in Woof he probably needed to modify a few things, but again, not enough to matter. The actual binaries are still the same (where they weren't upgraded anyway).