Grouped booktables are awesome - they look very nice and give the reader and quick overview (except for std.traits).
However, it repeatedly happened that when new symbols get added, these booktables aren't updated.
Two ideas:
For all modules with a booktable
1) Parse the public symbols and check whether all have been mentioned in the module comment (a simple `find` could do)
2) Use a Group: xxx key in the function comment header and build the booktable as postprocessing of Ddoc.
Probably doing (1) as a DScanner check is the easiest.
https://github.com/dlang/phobos/pull/5570/files