Why is this stow- and runable?

The first WRITE is not unknown to Natural.
It defaults to the physically preceding GET.
Hence the output, and no 434.

Even if they were both READs, with both END-READs after the three WRITEs, there would be no 434. Natural would default to the innermost READ, which would be VIEW2, or FALSE.

However , still working with READs, if you put a non qualified TKS after the second end-read you would get a 434.