The £8million Swede struggled to justify his price tag in his first two seasons at the Reebok Stadium but seems to be flourishing under Owen Coyle.
He scored twice last weekend against West Ham and looked sharp against Fulham and Southampton in the Carling Cup.
"I can't praise Johan enough how he has kept his head through all the criticism, from former management and critics all over the country," said Steinsson.
"I have been praising him because I know what he is capable of. And this is what we see day in, day out in training.
"I played against him before he came over here and I have said from day one that he's a fantastic signing.
"It's been just about finding the right person to get the right Johan Elmander out there - and this manager and this backroom staff is doing it."
Steinsson hit back at former manager Gary Megson, who signed Elmander, for stating in a radio interview last week he was keen to get back into football so he could go to the Reebok and win.
Megson also defended his much-derided reign at the club, claiming those who criticised him were "a bit dense".
"We are a changed team. We play differently, we have different aspects to our game," Steinsson told the Bolton News.
"We have been boosted with self-belief from the management and as players, put a bit more pressure on ourselves to perform.
"I'm pleased to see how we have improved - and any criticism against the players, no matter who it is from, if it is related to Bolton Wanderers, it should be going in one ear and coming out the other."