TWO HALVES IN ONE
Interesting puzzle today. The diagonal GREATDIVIDE (27A: Passage from life to death) (couldn't/shouldn't this have been clued geographically?) splitting the grid was novel, and the "secret code" of BACKINBLACK (1980 hard rock album that went 22x platinum ... or a hint to how to cross this puzzle's 27-Across) are just the sorts of things you expect from a Sunday, but there were so, so many three-letter answers, and a few real clunkers (NUTTED), that overall, the solve ended up being less than totally satisfactory.
On the bright side, Frannie liked the inclusion of the not-often seen word SUITORS (22A: Ones with bouquets, maybe), and CONCLAVES (60A: Private gatherings) ain't so bad either. In fact, much of the longish stuff (9s & 10s) was very good. MENTALNOTE, LOSSLEADER, BLOSSOMED, all nice. And who doesn't love an OCELOT (70A: Cat also known as the dwarf leopard)? Oh, and speaking of animals, I looked up MAKO (79A: Ocean menace), and found it is a variety of shark. They can jump 30 feet in the air, and some estimate that they can swim at over 60 miles per hour. Calling them a "menace," however, is challenged by at least one Wikipedia contributor, who wrote: "The mako is regularly blamed for attacks on humans and, due to its speed, power and size, it is certainly capable of injuring and killing people. However, this species will not generally attack humans and do not seem to treat them as prey. Most modern attacks involving mako sharks are considered to have been provoked due to harassment or the shark being caught on a fishing line." Sooo... maybe not their fault.
Lastly, 18D: "Purple haze" was LSD? I guess I should have figured that out, but I never really gave it much thought.