The phrase "a common tactic is" is correct and usable in written English.
It can be used when discussing strategies or methods that are frequently employed in a particular context or situation.
Example: "In negotiations, a common tactic is to start with a high initial offer to leave room for concessions."
Alternatives: "a typical strategy is" or "a frequent approach is".
If someone wants to emphasise the simplicity of a task or process, a common tactic is to compare it to either brain surgery or rocket science.
A common tactic is to roast the duck until the legs are tender, then make a sauce to compensate for the dried-out breast.
A common tactic is the "carry trade", borrowing money in a currency with a low interest rate and investing the proceeds in a country with a higher one.
"Who's the hottest property inside their small circle?" A common tactic is to host a gathering not in honor of Mr. Obama, but for someone close to him, such as one of his top aides, making it difficult for him to refuse the invitation, one Washington hostess slyly suggested.
A common tactic is to pull a remark out of its original context and depict it as meaning something the speaker never intended.
A common tactic is for the scammer to claim some affiliation with HAMP and promise to get the homeowner's debts or monthly payments lowered, in exchange for payment up front.
A third common tactic is sidelining people who were in the know by placing them in marginal roles.
Their common tactic is scorn, ridicule, and contempt.
Common tactics were beatings, arrests and tax audits.
A common tactic has been to post "no parking" signs in oblique spots, often with lettering that can only be read close up, in what drivers' organizations have said has amounted to entrapment.
While their surveillance techniques might not be in the league of the NSA, corporate monitoring of citizen-activists has become a common tactic, and there's been a significant amount of investment in this area.
