write a formula like:
totext({table.dateField}, "MM/dd/yyyy") + {table.Acronym}
this should group by date and description, and whenever either changes, it will change the group, as well as sort it, though your acronyms may interleave because of the date. If so, you can do 1 of 2 things, 1) create a higher group based on acronym alone, or 2) reverse the order of acronym and date in the above formula. Oh, yeah, I forgot the important part, group on the formula instead of a table.field combination.
HTH