The phrase "a tactic that has worked" is correct and usable in written English.
You can use it when discussing strategies or methods that have proven effective in achieving a desired outcome.
Example: "After analyzing our previous campaigns, we decided to implement a tactic that has worked well in the past to boost our sales."
Alternatives: "a strategy that has proven effective" or "an approach that has been successful."
Catholic bishops called separating families "immoral" and floated the idea of holding prayer vigils in front of federal courthouses — a tactic that has worked in opposing abortion clinics.
It's a tactic that has worked so far, and Hastings is banking on the world's appetite for top-notch TV being far from sated.
If that doesn't work, they will raise the specter of Japan gaining a lead in the technology, a tactic that has worked in the past to elicit Government funding for semiconductors and computers.
It is a tactic that has worked well for years and these two threats of action are just the latest in a long series of similar disputes, most of which get resolved without a walkout.
In this case, the critics fell back on the familiar ground of attacking my patriotism and that of The Times, because it's a tactic that has worked for them in the past, and because it's safer ground than having to debate painful truths about the war and its human toll.
Beijing has been making a determined effort to peel them off, using a tactic that has worked well for it in Africa gifts of sports stadiums.
Tiridates then resorted to a tactic that had worked well a century earlier against Mark Antony: he sent forces to raid the Roman army's supply route, which stretched over the mountains back to Trapezus in the Black Sea.
The Christmas season, of course, furnishes the perfect time-tested tactic that has worked for decades for department stores: Santa Villages and other Christmas extravaganzas for which people gladly pay to give their kids a festive experience.
For the Sierra Club and other groups attempting to block all new fossil-fuel plants in the United States, the decision to abandon Avenal came as a signal: the tactics that have worked against the coal industry, which has not won approval for a new plant in more than a year, can now be applied successfully to the expanding natural-gas industry.
But faced with a choice, Downing Street opted for the tactics that have worked so well for Cameron in previous crises: deflect, dismiss and deny until the story ebbs away.
The Incas expanded and projected on earlier, pre-Incan solutions and adaptations; in the process, many tactics that had worked well on a smaller scale became inoperative; others were reformulated in such ways that their original outline was barely recognizable.
