lt-proc -g now outputs # when input-side starts with #?

nob.dix has entries that turn things like `# opp` into ` opp` (for broken multiwords):
```sh
$ echo '^# opp$' | lt-proc -b -g nob.autogen.bin
^# opp/ opp$
```
The above is correct, the output-side has ` opp`.

They used to work fine in regular `lt-proc -g` too, but now the `#` is output (or it's treated as ungeneratable, not sure which):
```sh
$ echo '^# opp$' | lt-proc -g nob.autogen.bin
# opp

$ echo '^# opp$' | lt-proc -d -g nob.autogen.bin
# opp
```
(should output ` opp`).