Lletget, 23, originally joined West Ham in June 2009 after being spotted playing for local club Sporting Santa Clara and soon established himself as one of the club’s most promising talents.
Despite his recognised potential, though, the California-native ended up making just senior appearance in six seasons at Upton Park – in a 5-0 FA Cup defeat at Nottingham Forest, before returning to the States earlier this summer to link up with the MLS Cup holders.
His time in London also coincided with Grant taking the club down to the Championship following a dismal 2010-11 Premier League campaign – but not before pushing the former US Under-23 international out of first-team contention.
"Grant, he was a mess. It's the truth," said Lletget. "It was just unorganized. As far as preparation, he wasn't the best. When he was there, he pushed me off to the side."
Lletget, meanwhile, has enjoyed a stellar start to life with the Galaxy since joining the club in May, having established himself as the first-choice starter on the left wing alongside Steven Gerrard and former West Ham teammate Robbie Keane, while also bagging eight goals in 19 competitive appearances.
As well as earning strong support for a first senior international call-up, his impressive performances have also left those around MLS wondering how he did not see more action with the Hammers, and the versatile midfielder admits that he is just as puzzled.
"I always felt that it was just an arm's length away," he told ESPN FC. "It was always there, but for some reason, there was always something that was holding me back, just a break, an opportunity, a breakthrough, something. I couldn't put my finger on it.”
A loan move might have helped his chances but, for some reason, no concrete offers for his signature ever materialised.
“No one would ever say, 'Here, sign with us,’” he added. "As time goes by, you get older, and people go, 'Why isn't anyone taking him on loan?' Then they don't trust it because they don't want to be the first. It doesn't matter what the player does."
Nevertheless, Lletget is fast proving one of the signings of the season in MLS and, with LA looking like a good bet to claim an unprecedented fourth title in five seasons come December, he should have few regrets about his decision to head back across the Atlantic.
There is even a strong argument to make that he is proving far more influential to Bruce Arena’s side than fellow summer signings Gerrard and Giovani dos Santos at the moment and, should he keep up his current form, then it will not be long before he earns that first US cap.