Allyn Gibson wrote:
We had a discussion at work about split seasons, and we were trying to figure out who to blame. (My coworkers were upset at the midseason break for The Walking Dead.) The thing is, no one's to blame. American television has always had split seasons, it's just that we never advertised them as such. Shows usually take a breather in the schedules during November and December. The networks use that as a time to put specials and other events on the schedule, while the programs can catch up productive-wise and build up another bank of episodes. It was always an informal thing, but shows like Battlestar formalized the broadcast break into a narrative break.
In the past, a show traditionally began in September, continued airing new episodes until the end of November, then took a break for December. After that, you could be guaranteed of new episodes in February, but otherwise the remainig episodes of the seasons would be stretched out so that the season could last until May.
These days the episodes are clumped together, which usually means splitting the season in two halves. With some shows like Lost and 24 it was felt that a mid-season split actually hurt them, and they actually did air all episodes consecutively, with a season starting in January and ending in May.
Maybe I'm ignorant here, but it does feel like BSG and the Stargates were the pioneers of the mid-season split with having mid-season cliffhangers. Hell, I'm fairly certain BSG started the tradition of releasing half-seasons on DVD.