Hey, I'll try. Destructions are sometimes thought to be an "ending" to an altercation. Or used in such a way that the attacker's weapon (ie their hand from a jab) is no longer functional. These kinds of definitive destructions are rare and VERY unusual. Rather, destructions are simply a tear in the fabric of time in that fight where you can enter more safely to end things. An example of this may be....They throw a straight punch (SP, Cross or jab) and we siko or elbow it. In essence let it run into our elbow. This moment of pain and this interception allows a small window that we follow with tremendous amount of pressure, (ie straight blast or ABC) Attack By Combination. Think of this as in FMA this is the proverbial kitchen sink. everything is thrown that they are overwhelmed and off balance and unable to counter attack. In JKD it's an 50 MPH blast down their centerline. From there it's HKE. Major tools. Fight enders.
Destructions can be against anything not just their attacking weapons, It can be intercepts, stop hits half beat attacks etc, The form of eye jabs shuffle kicks, shoulder stops etc. The key is such a total way of training that incorporates everything into this one area. How we move, how we train, how we hold our guard, where we place our guard JKD 5 ways of attack, JKD premis and FMA technique as well, It includes weapons training and drills from Panantuken, Panajakman. If done correctly they are easily pulled off. Of course it is always dependent on your opponent and how well they fight, This said, we have to have more tools and be much more adaptable. This is why we weapons spar from many different combinations of weapons and go from there to empty hands to the ground etc.
Hope this helps