Watching a bunch of arrivals at Vancouver, I got a lot of shots of aircraft reversing thrust. Current jets fall into one of two categories. Cascade reversers or bucket reversers. The bucket reversers aren’t quite as obvious as those fitted to the old 737-200s where they clamped across the whole exhaust but the effect is much the same. Bucket reversers look like they are doing the job to me. They hang out and you can imagine the flow being turned around as they power up. Cascade reversers are far more subtly as the nacelle translates aft and the flow is redirected out of the based of fins that is now exposed. I imagine they are similarly effective but I have no data to back that up. If someone knows more, please let me know as I am genuinely interested to find out.