The phrase "had extensive discussions" is correct and usable in written English.
You can use it when referring to an extended period of conversation or dialogue about a particular topic. For example, "Our team had extensive discussions about the upcoming project before making a decision."
We have also had extensive discussions with the NUJ, providing them with assurances on their concerns.
"We had extensive discussions," she said, "about the need to enforce intellectual property rights".
But the Nationals had extensive discussions with Fielder and his representative, Scott Boras.
We've had extensive discussions with companies that have hundreds of millions of customers, and yes, it can.
Mr. Poll said he had extensive discussions with 20th Century Fox about a script involving a struggle among such fictional characters as Allan Quatermain and Sherlock Holmes.
But while preservation advocates acknowledge that they have had extensive discussions with Lincoln Center, they say the talks have had little impact.
Of the five focus groups among black physicians, all had extensive discussion regarding the importance of race for medical decision-making.
Chapters 2 and 9 have extensive discussions of the evidence for the roles of the sun, greenhouse gases, and other factors on global climate.
Shouldn't we be having extensive discussions, protesting, implementing solutions?
In an ideal world, we would have liked to carry out more open ended discussion of intervention delivery strategies, but it would have been unethical to have extensive discussions on who should deliver the intervention because we knew that this would be constrained by local resources.
Instead, Durbin pointed to one of the items Boehner is proposing to leave on the table in severing the payroll issue, and about which he also may need to have extensive discussion with his caucus.
