Boosting method with two controllers:
Select Series and create a new competition. Select a Five5 match and a 10 game series. The quality of the teams doesn't really matter, but I chose England v Malaysia.
Player 1 for the achievement and player 2 (I just used my main profile as a guest) as the booster. Make sure player 2 bats first, either by winning the toss and choosing to bat, or if player 1 wins the toss then just select bowl with player 1.
You cannot declare straight away, so face 1 ball, defend or let it run through to the wicket keeper, then declare at 0/0 or 0/1. With player 1's innings, just score the 1 run needed and you're home and hosed. Each game - with loading times - takes about 90 seconds, so you can get this done in around 15 minutes.
Also, it is worth noting that if you make a mistake with the toss and accidentally bat first, it will be quicker to take all the wickets rather than see out the five overs. You only need to take 5 wickets in Five5, so just bowl at the stumps and leave the second controller untouched.
With 1 controller:
Use the same set-up with a series of 10 Five5 games, but change the settings to easiest. Whether you're chasing or batting first, this will be a doddle. Chasing should maybe take 2-3 overs to win. Find a good podcast and mute the game.
Happy hunting to all.