Use of before and forwards are inconsistent with the rec.
"Sometimes an initial capital extends before the start of the text as well as perhaps continuing for several lines."
and
"If the value is negative, an implementation MAY interpret it as as "dropping" forwards."

Suggest 
"Sometimes an initial capital extends  the start of the text in the before direction as well as perhaps continuing for several lines."

"If the value is negative, an implementation MAY interpret it as as being in the after direction"