SRAM's 12-speed Eagle proves that a one-by drivetrain can match or better the range of a multiple-chainring transmission, which in turn, has doused any hopes that the front derailleur's smoldering embers will ever be rekindled. Eagle was a must for the Chicago-based parts maker, because its premier XX1 ensemble could not match the range of Shimano's sharp-shifting two-by drivetrains, and descriptors like "virtually," "similar to," or "nearly," are not the vocabulary of a winning team. The addition of a 50-tooth cog to its 10 by 42, eleven-speed cassette provides a 500-percent gearing spread, which exceeds Shimano XTR and XT's ranges and thus, should silence all doubters, even the staunchest two-by holdouts in Germany. That twelfth cog, however, may have consequences that reach beyond range and MSRP. [Keep reading at PinkBike]