And now his job has gotten even more difficult.
The Church of Jesus Christ of Latter-day Saints has announced that the minimum age requirement for church members' missions will be lowered. Men can take their missions at age 18, instead of 19, and women at age 19, down from 21.
For a men's basketball coach, that means that high school seniors who in the past went to BYU for a year -- either playing or as a redshirt -- and then went on a mission if they chose can now defer admission and go on the two-year mission first.
The player would then be able to stay at BYU upon returning for four or five years (if he were to redshirt) continuously. Of course, no one is made to go on a mission. Consensus player of the year Jimmer Fredette chose not to go on a mission. Former BYU star Danny Ainge didn't, either.
Rose said he has had players stay one year, leave for two, some go on missions, some not, and others go later in school.
"It's such a personal decision if you're going to serve or not," Rose said. "What this does is give them another option. I still believe we'll see more missionaries go at 19 or 20 or 21 but it will be interesting to see how it affects the players we sign."
The Cougars are counting heavily on Tyler Haws this season after he returned from his mission. He was one of their top scorers three seasons ago when he was a freshman.
Rose said Haws has returned in the best shape of any returning missionary. That's not always the case. There can be an adjustment period because the missionaries aren't usually playing basketball, sometimes at all, during the two-year absence.
"There are a lot of players we're involved with right now where that could be an issue," said Rose.
The most important recruit -- Chicago's Jabari Parker -- now has the option of deferring his enrollment and going on a mission after his senior year in high school. Parker reduced his list to five -- BYU, Duke, Stanford, Florida State and Michigan State (in no particular order) -- last week. Of course the expectation is that Parker would still go to school and then to the NBA, where he is projected as a possible top pick in 2014. But Parker now has an option.
"There is going to be a transition period while players decide how they're going to handle this," said Rose. "We have a spreadsheet that is very complicated and gets very full as we look at the next two or three years depending on the decisions they make.
"They can serve right away now, play one and then serve, not serve, come for two years and serve and then come back," said Rose. "For 2013-14, 14-15, 15-16, there could be some real challenges in the process. We'll try to get a good idea of what these players want to do."
But Rose said serving is a personal decision within the family and has a lot to do with the maturity of the individual. He said a lot of families would rather their son go to school for a year and deal with being homesick and then go on a mission, where it's much harder to be away for two-year period.
"You want your child to be comfortable and have them work through the homesickness first," said Rose. "These are personal decisions the families have to make. You have to get a feel that your child is ready to go out on his own. Every player has to decide this for themselves. My role as the head coach at BYU is to support it 100 percent. I tell them all make a decision and we'll support you."
Rose said it's hard to tell the advantages or disadvantages yet on when a player serves a mission. Regardless, the seven-year clock for BYU players -- four seasons of eligibility in a five-year period with the additional two missionary years -- hasn't changed.
"We have a group of players in the class of 2013-14 that we hope to sign in November and once they sign we'll go through to see what their individual situations will be," said Rose. "We've had it all here. Jimmer Fredette was the player of the year and didn't serve. We've had players leave and come back. Now all the options are available. So we'll have to see how it plays out."
Editor's Note: For more on how this might affect the recruitment of Jabari Parker, read Eamonn Brennan's take here.