O2 sensors causing a choking in power? I don't think that's what he meant.
I mean, if you have bad o2 sensors, you should get a check engine light, and your air/fuel mixture will be off a tad (nothing extreme, though, not enough to choke you out at 5000 rpm, but I've been wrong before).
Your car does have four catalytic converters that can get clogged, however, and having clogged cats can hinder your performance...