Something thats often overlooked about Choice Band/ Choice Specs is how effectively they can be used defensively. Your immediate response to that is most certainly NWO is an idiot, but I'll explain.
Choice Band/ Specs pack incredible power, and put a ton of offensive pressure on the opponent. However, one of the biggest problems with them is misprediction. For example you are using a Choice Band Dragonite and come in against Heatran, your opponent has a Salamence in the wings. If you opt to Outrage, and Heatran stays in, the opponent can screw up Dragonite big time with Toxic or Will-o-Wisp. If you opt to Earthquake, and the opponent switches to Salamence, you are suddenly faced with tremendous offensive pressure.
Here's where the use of Band/ Spes on a defensive minded team has its boons. Choice Band and Choice Specs are bound to force a ton of switches, nobody wants to eat CB Close Combats and Specs Hydro Pumps, and the opponent will inevitably switch to a resist. But coupled with heavy entry hazards, this can be heavily abused, especially on stall teams which rely heavily on hazards and phazing to deal damage. Band/ Specs act as pseudo phazing, allowing you to slowly beat down opposing pokemon throughout the course of a match. The opponent is now faced with the decision: do I want my pokemon in right now to die, or do I want to switch, take 30% just for coming in and potentially be KOed the next time round?
This strategy can be employed very easily on a pseudo stall team. Stack up entry hazards early on, then get in a Band/ Specs user to put tremendous offensive pressure on the opponent. This is especially useful against the bulky sweepers that often give stall teams trouble. These offensive threats can be worn down throughout the course of a match from entry hazards or being forced to eat powerful moves. With Band/ Specs, even resisted attacks are going to put huge dents into most pokes.
Stunt Stall is a great exemplar.
The best part about abusing Band/ Specs on a defensive natured team is that you eliminate one of the items' biggest problems: prediction. Now, you wont have to take risks such as Lucario staying in on Terrakion's X-Scissor and sweeping your team because. You can safely make the obvious move with relatively few consequences. If Lucario stays in, its gonna die. If Mew comes in, it'll be punished with 37.5% from entry hazards and be 2HKOd anyways. All in all, Choice Band and Choice Specs make threats to defensive minded teams much easier to deal with.