I've noticed some strangeness in flare behavior when strafing around target behind columns. After I lose LoS to target, flare goes away to a totally unpredictable location within the room. When I restore LoS, however, flare reattaches to its victim in a moment. This makes this bug somewhat less noticeable---flares are supposed to be stickied onto their victims, and they disconnect only when you can't see it, while seemingly staying there when you watch.
However, the damage that flare should be dealing (that's around 200 hp!) goes away as well. If you (somehow) pack ten flares into something that doesn't die of direct impact of ten flares, and hide away, expecting it to certainly die (around 2000 hp burning over time), you might be surprised that it will not lose anything after you leave.