Vertical Metrics - New Body Height Question

In Version 3, I noticed that “Body Height” was added to vertical metrics. Just looking for a quick explanation of how Glyphs uses the new “Body Height”. Would vertical metrics (starting from bottom to top) go from Descender to Baseline to x-Height, to Cap-height, to Ascender and then to Body-Height, so Body Height would include any extra leading and accent space above the ascender? In the past, I might have extended the ascender to include any extra leading and accent space. What is best practice? Thanks.

Only the common values (ascender, descender…) will be written to the font. All the others are more a design aid. They will be used more in the future.