I had a stereo with SMD parts, and I guess for ground plane reasons, they had ~0.2mm traces of solder+mask, passing under the middle of all SMD parts. And during soldering/de-soldering for troubleshooting the stereo, and bad flux, I ended up with a bunch of unmasked edges, right under the RC parts and fine pitch quad op-amps. What a nightmare.
I wish I had a good way to test SMD caps, in circuit. Or for some stuff, I should pre-heat the PCB in an oven, then use air and just mass decap a few things I have. I don't have anything I suspect bad SMD caps on really, but in general, if WW3 starts, it will be worth the time to check all SMD caps.
Probably the most import thing's I've SMD de-capped, was the circuits for the controller chips, of computer SMPS. Then I got all the sizes, to plug into LTspice and try and make ideal models of the controller chips.