1964 actually--at least until the last two weeks of the season.
I agree generally--the sport has to find a way to attract new fans. No one gets excited about kickoff changes in NFL. Just a note on hockey that they actually extended the regular season games with OT and shootouts--used to be ties until 1983. But the OT has always been limited except for playoffs.
Right, I'm a diehard football fan (moreso than baseball, actually, as the ordering of the username suggests!) and I'm generally not a fan of NFL rules changes over the past ten years but recognize my traditionalist biases there. None of them have fundamentally changed the game, even when Bill Polian whined and changed how DBs cover receivers. DH plus runner on second is a fundamental change.
Also a minor quibble, but why not put a runner on first instead of second? The latter means that if the away team records two outs and gives up a single, they lose. Seems unfair to me.