This is definitely true and the biggest problem I was having was discipline. Instead of working on one photo at a time including resizing and saving as JPEG, which is a huge time waster, I could have culled, processed in ACR (pretty much the same in Bridge and LR except presented differently) and then save to JPEG in a batch.
So in some sense moving to LR doesn't inherently change that b/c I could still be working with an inefficient workflow and wasting lots of time.
So from my perspective, it's primary the LR interface that I've finally come to understand because I've been using Bridge for a very long time and didn't want to try anything different. The fact that I can use the same plugins that I use in PS in LR is also a big plus as well. Photoshop will remain part of my workflow for when I need more advanced editing using layers, etc. But I would estimate I can stay in LR 90% of the time, especially with having my PS plugins in LR.
Personally I gave LR a go three times, including buying a book by the Lightroom Queen. I just couldn't get used to the slow workflow it imposes.
I cull using FastPictureViewer, I think it doubles my speed compared with Bridge.