troffrc conflicts with .nh

[Lyndon Nerenberg]

I'm running groff 1.17.2 on FreeBSD 4.7. The problem seems to be
generic to groff going back to at least 1.14.

I've found it impossible to disable hyphenation, either through '.nh'
or '.hy 0'. troffrc's use of .hpf seems to be the culprit.

The .hpf commands appear to act as if each pattern in the file was
specified via a .hw-like request, thus overriding any no-hyphenation
commands. This behaviour is wrong. The patterns loaded via .hpf need
to be loaded into a namespace distinct from that used by explicit user
hyphenation requests (e.g. .hw or inline hypephenation of the source
text), and the .hpf-loaded rules should only apply when hyphentation
is in effect.

--lyndon