If you ever become tired of hearing Modest Mouse on the radio, just remember what could be on the air if “Float On” wasn’t. The group’s 2004 hit took precious spins away from Avril Lavigne and Hoobastank, proving that quirky indie-rock bands still had a fighting chance to make a substantial commercial impact. The group’s addition of Smiths guitarist Johnny Marr for 2007’s We Were Dead Before the Ship Even Sank injected some new vitality into the mix, but it looks as though Marr will be M.I.A. (no, not the previously pregnant one) for Mouse’s spring tour. With the flighty Brit engulfed in work for the next Cribs album, former Grandaddy axeman Jim Fairchild will help the show float on.