>> Secondly, I couldn't find where the DD register is documented.
>> It's present neither in the MS man page nor in the groff online
>> manual...
>
> Agreed; there needs to be an entry in the "Document control
> registers" section of 'man groff_ms' (which does have an entry for
> PD, etc.).
Larr
>> Ted Harding:
>>
>>> If you are using ms macros, then there are two number registers
>>> to watch out for: \n[PD] "paragraph drop" and \n[DD] "display
>>> drop". \n[PD] defines how much vertical space will be inserted
>>> before starting a new paragraph. \n[DD] defines how much vertical
>>> space
