OBS Again (and again and again etc.)

[Four Seam]

I agree with your interpretation, which I read to mean that by making the runner do anything other than run across the plate and step on it, the catcher has impeded the runner, therefore obstruction has occurred per the rule.

Seems to me that when the runner reaches a base or home plate so that her next step would be on the base, if there is a fielder (or foot etc.) between her and that base who does not have the ball, that fielder has impeded her progress. I don't see that you have to have contact to have obstruction...if the fielder is in the way when the runner gets to the base, the fielder has impeded the runner. If having reached the base, that is, she is close enough so her next step would be on the base if there were no fielder there, she slides or jumps over the base, or even if she stops to avoid crashing into the fielder, she has been impeded.

Try this analogy. I come home from work and find a moving van parked across my driveway. When I am a block away I am not impeded. But when I drive up to where I turn into my driveway, and can't go there because the van is in the way, by any reasonable meaning of the word, that van has impeded me. I wouldn't have to crash into the van, or drive around on my lawn, I'm already impeded because I can't continue on my path into the driveway.