You're breaking my heart! Literally, HEART in the middle of THE ART OF WAR, separating by one square at a time. I appreciate the extra layer, helping to elevate this from the standard "hidden words" pack.
Great theme phrases, too. HEAD FOR THE HILLS almost felt related, referring to the eternal struggle between the HEAD and HEART. It's been a minute since I've heard IN THE AIR TONIGHT, but the tune snapped right back.
I'm hoping that the earworm will head for the hills soon.
Like Kim mentioned, I would have loved for the final themer to have the HEART broken further to the right, completing a progression from NW to SE. I was surprised to find that there are few possibilities for that last one. Couldn't find anything that was 15 letters, but WEATHER CHART or THE DEPARTED would work with a matching length.
I love the notion of the shaded squares looking like a heart (when turned sideways)! You can always "flip" a grid along the NW-SE diagonal, making Across answers Down and vice versa, so that would have accomplished it.
Will Shortz doesn't often take puzzles with the same letters in sets of circles or shades, because it becomes too obvious. Once you realize the HEART letters will fill the second set, you can plunk them into the rest. I wondered, was there a way to avoid this? I doubt it, since without the shaded squares, it'd be impossible to figure out.
Five themers, with three spanning the grid, is no easy feat. Well done to incorporate CHEF'S HAT, a delightful entry. Even more impressive when considering it strings through three theme answers. There aren't many possibilities. Our word lists have only that one entry for the C??F?H?? pattern.
With a theme set like this, the problems usually occur when you get to the perimeter, having to work through two themers. Take the bottom right, for instance. The K in LIKES makes it even tougher, and few constructors would aim to end with LOEIL in their grid.
Not the smoothest ride today, but full of ups, what with all the pizzazz in the themers and bonuses. Appropriate for a puzzle about love and heartbreak.