The phrase "already proving effective" is correct and usable in written English.
It can be used to indicate that something is demonstrating effectiveness at an earlier point than expected or previously stated.
Example: "The new marketing strategy is already proving effective, leading to a noticeable increase in sales."
Alternatives: "already showing results" or "already demonstrating success."
These iris recognition systems are already proving effective at London's Heathrow Airport and Amsterdam's Airport Schiphol, and they are scheduled for installation this year at 11 Canadian hubs.
Other modern technologies, including radar and satellite imaging, are already proving effective in the land beyond the temples at Angkor, in Cambodia, and in surveys of the Nile delta and ancient irrigation systems in Iraq.
The report concluded intelligence sharing with international police forces was already "proving effective".
But there's something else at play here, too: Target is strengthening a connection to its customers that is already proving effective and necessary.
While our solutions should be local, based on each region's unique needs, we should replicate programs that are already proving effective.
The plan is based on a series of measures that are already proving effective in keeping women and children healthy from preconception and pregnancy through to childhood and adolescence," said Dr. Elizabeth Mason, Director of the Department for Maternal, Newborn, Child and Adolescent Health at the World Health Organization.
Schools and communities should adopt prevention approaches already proven effective.
Moreover, people are comfortable with strategies that have already proven effective.
After painting a stark and unsettling picture of our current quandary, Heal outlines simple solutions that have already proven effective in conserving nature and boosting economic growth.
The Vice team's combination of an understanding of their readership with a counter-culture philosophy has already proved effective in print and online.
The environmental conservation commissioner, Erin M. Crotty, said the governor's bill would strengthen and expand existing cleanup standards that have already proven effective in New York and other states.
