Joe Allen and Scott Sinclair left the Liberty Stadium for Liverpool and Manchester City last summer, but have endured mixed seasons affected by injury, form and managerial selection.
Dyer, by contrast, has helped Swansea to the Capital One Cup and his form has led to talk of a call-up to the England squad.
The 25-year-old is aware of how Allen and Sinclair have fared since they took flight from the Swans, while Leon Britton has fared better since returning to south Wales from a six-month stint at Sheffield United.
"I've seen players that have gone and not done so well," says Dyer. "They said it was the hardest decision that they had ever made. The thing is, they know what they are going to miss in terms of playing football.
"Britts went and came back and he's done fantastically well. It's hard but you never know what's going to happen.
"I've seen the run up to when players are leaving. You get to experience the whole thing with them. I'd look at what happened to others if I was in that position.
"Anyway, I'm enjoying my football so much I've not thought about the future. I've got 18 months left so I don't think it's high on the agenda at the moment."
While Allen and Sinclair departed Swansea, Michu arrived from Rayo Vallecano to spearhead the attack under new manager Michael Laudrup. The Spanish striker bagged 14 goals in his first 22 games, and despite a dip in form that has seen him hit the net only five times this year, Dyer is confident he will return to form soon.
He said: "Michu is going to score more. But as long as we're winning matches he's not too bothered.
"And he's the calmest guy I've known. He's not bothered about anything. I've never seen anything like it before. He's in his own world sometimes."