"has certainly delivered" is correct and usable in written English.
It is typically used to indicate that something has been successfully completed or achieved. Example: The new marketing campaign has certainly delivered on its promise of increased sales.
Shareholder value maximisation has certainly delivered for the top 1%.
His first term has certainly delivered its share of economic happiness.
He promised a sharp change in the moral level of the Presidency, and he has certainly delivered that.
(Although, since the cafe has been covered by everyone from the New York Times to Al Arabiya it has certainly delivered on that front).
Peter Capaldi's second series in the title role, Steven Moffat's fifth as showrunner and Jenna Coleman's last as Clara has certainly delivered bold moves and changes.
— Senator Mitch McConnell has certainly delivered for this western Kentucky community, where an esplanade called McConnell Plaza wends along the Ohio River waterfront, which is being spruced up with government help.
Starbucks has certainly been delivering more of a pleasant jolt than Coca-Cola has of late, but the Atlanta soft-drink giant rewarded Coke shareholders twice as handsomely from 1982 to the 1998 peak.
"It has certainly retained its ability to deliver centrally directed attacks here in the U.K. In case after case, the hand of core al-Qaeda can be clearly seen". Morocco also continues to keep up its guard.
Brixton has certainly struggled.
Van Bergen needs to do a lot more than that to deliver the Bill Gates-style wired home to the masses, but he has certainly made a promising start.
He needs to do a lot more than that to deliver the Bill Gates-style wired home to the masses, but he has certainly made a promising start.
