Sean's withdrawal removes arguably the biggest obstacle to the appointment of former England boss Andy Robinson, who is the bookies' favourite.
Reports claim the Edinburgh head coach will confirm tomorrow whether he is going for the job, with the deadline for applications now less than a week away.
The 45-year-old has been given a ringing endorsement from the Glasgow coach, who said today: "I would be amazed if he didn't (apply)."
Sean, who has worked alongside Robinson as a coach in the international set-up, added: "He's great; he's very hands on.
"I've learned a lot from him from doing one on ones with the players.
"He knows a lot about the game, is very, very enthusiastic about the game and very passionate about rugby and about his team - whatever it is - winning and getting the best from the players."
While Robinson might now appear the only viable candidate, the Scottish Rugby Union were keen to avoid a coronation and advertised for the position.
Sean agrees with that decision, saying: "Obviously, it's got to be worldwide; you've got to go through the procedures and who knows what that throws up?
"But I've worked with Andy; I know what he can do."
Despite pulling out of the race this time, Sean desperately wants the top job at some point in his career.
Asked when that might be, he said: "I'll know.
"And it's up to me to force the issue and make sure that I'm in the frame.
"But, at the moment, you look at where we are and you look at where Scotland is and there's a candidate there."
The 47-year-old, born in New Zealand but capped 29 times by Scotland, added: "You look at where you are in the coaching spectrum and I'm still learning.
"I've still got a long way to go and I'm working hard, learning with Glasgow.
"This is my third season with Glasgow.
"I'm big enough to admit I've made mistakes, I'm moving in the right direction and it takes time to build a squad.
"I'm really excited with what we've got.
"When you look at other candidates, what they are and what the Scotland team needs at the moment, it's not me and I think I need to concentrate on Glasgow."
Robinson's candidacy has not met with universal approval.
Despite being part of the England set-up which won the 2003 World Cup, the team went backwards at an alarming rate once he took charge.
But Sean said: "We tend in Scotland to look at the bad things: Andy not having done that well with England.
"But when you think in our back yard, we have a World Cup-winning coach..."
Sean also ruled out becoming Robinson's right-hand man should the Englishman get the job.
He said: "I think Andy's got his own ideas of what he wants to do if he does apply for it."
Glasgow captain Alastair Kellock is relieved his coach is staying put and dismissed suggestions the latter's appointment as Scotland boss would have enhanced his own Test prospects.
"I think my prospects are in my own hands, regardless of who the coach is," the lock said.
"I've got to be playing well and hopefully the coach - whoever it is - will pick me."