As the NPRM went through the comment process, an argument developed for additional weight. Among the reasons cited were that more weight would allow for currently produced type-certificated four-stroke engines and ballistic parachute recovery systems. Ultimately, the FAA acknowledged that the added weight might be a safety benefit to light-sport aircraft design. It was determined that a max gross weight of 1,320 pounds would suffice. By chance, this figure qualified certain standard-category aircraft that met that weight, like a Cub or Champ, for Sport Pilot certification. As you can imagine, this spurred more discussion, including why Cessna 150s, one of the most prolific trainers, couldn’t be included.