The throttling is new. They may be doing that to discourage people scrubbing their accounts, though it could also be a load issue since a lot of people have been doing.
When I did it last weekend it seemed to work fine. I had to run it a couple of times, and it took a while, but in the end it seemed to get everything.
I used PowerDeleteSuite to edit and delete. You can configure it to just edit if you want.
Edits seem to be throttled to one every 5 seconds. I ran powerdeletesuite several times and it got most of my comments, but still not all.
The throttling is new. They may be doing that to discourage people scrubbing their accounts, though it could also be a load issue since a lot of people have been doing.
When I did it last weekend it seemed to work fine. I had to run it a couple of times, and it took a while, but in the end it seemed to get everything.