The France international defensive midfielder left Tottenham for Premier League rivals Watford in the summer transfer window.
“We've all been impressed by Watford's front two but I love watching Ben Watson and Etienne Capoue in the midfield engine room,” former Tottenham midfielder Redknapp has written in The Daily Mail.
“Capoue was so casual at Spurs but with Watson in the middle of that 4-4-2, they have the energy and the drive to push Watford on. It's hard work but they're more than happy to do it.”
Capoue was on the books of Tottenham for two years from 2013 until the end of the 2014-15 season.
The 27-year-old struggled to make a huge impact at White Hart Lane and failed to play regularly.
The Frenchman scored one goal and created three chances in 12 Premier League appearances during the 2013-14 campaign.
Last season, Capoue featured just four times in the league for Spurs, creating four chances in the process.
The former Toulouse star has been in much better form at Watford so far this term and has been playing regularly.
Capoue has created 15 chances in 17 Premier League games for the Hornets. The midfielder has a pass accuracy of 79% and a shot accuracy of 31%, and has won 17 headers, 30 dribbles and 34 tackles.