Expert Campaign Multiplayer Perspective: This card's best usage is in a 3-4 player game where the group is bringing a considerable amount of player side-schemes. Generally, most player side-schemes don't make it to the table at my sessions due to the amount of investment it takes to clear them. At best, 1 or 2 hit the board early-game and then players have to start spending resources building their own boards and managing the regular problems that the scenario throws at you. Containment Strategy allows your team to load the board with player side-schemes and all but guarantees they are defeated at minimal cost. It changes the outlook from "I'll play this side-scheme and hope the team has enough wiggle room to get the pay-off" to "I'll play this side-scheme and I will 100 percent be getting 20 thwart, 20 damage, a specialization, or 4 free supports for 1-cost".
Now just because this card's best usage is player side schemes doesn't mean that's the only situation its worth playing in. In multiplayer, side-schemes are far more common due to the amount of encounter cards drawn each turn and their threat values are fairly high. There will be many situations where your team doesn't have an efficient way to deal with them. Enter Containment Strategy. Some people will fall into the trap of thinking that because this card can single-handedly deal with a scheme over several turns, that's what has to happen. In reality this card only needs to remove 2 threat to put it on par with For Justice and Crisis Averted from a thw/resource standpoint. Containment Strategy is especially useful when needing an extra chip to get rid of a Hazard Icon on a scheme. When paired with cards like Indomitable and Desperate Defense, Containment Strategy all but guarantees the table won't be seeing an extra encounter card. An encounter cancel for 1 cost is on par with Dr. Strange's Protective Ward.
This card is quite strong and should see play in many perfect defense style decks at at least 1 copy, but Cable deserves a special shout out. Askani'Son already incentives Cable to play defensively and the defense archetype has some inherent synergy with Cable due to cards like Desperate Defense having energy resource or cards like Back-Flip/Side-Step requiring energy resources for their full effects. Cable can run all of the player side schemes for this card to attach to and this card is an Upgrade. Upgrades and Events are extensions of a player's identity and thus the removal from Containment Strategy is treated as Cable's removal regardless of who defends. Cable's ready ability is once per phase so Containment Strategy is another method of triggering Cable's ready and can help with consistently clearing Technovirus Purge turn 1.