We have both bought and sold resale, and have encountered occasional aggravations both ways.
My sense in going through a few of these is that the transactions that were problematic were problematic from the start -- first one thing, then another. If we hit any early problems, we move on -- and I think that is good advice for both buyers and sellers. Early problems - to me - are BIG problems and the sooner you move on the better off you are.
We have done that both buying and selling. We withdrew our first-ever resale offer back in 2004 because the seller was playing games, and as sellers we've refused to respond to several offers because we were not comfortable with the buyers.
If everything goes fairly smoothly throughout, a minor delay at the end is probably, as mjc2003 said, just a personal scheduling issue that is easily resolved.
I also think that some brokers are better at this than others, and I know that some brokers are small outfits despite their pretentious names, and they are simply overwhelmed by the crush of business.
For example, on another thread I read someone post that they made an offer on a Monday, and it went to ROFR on Thursday. In our most recent transaction through TTS, we received an offer one afternoon, we and the buyer submitted our paperwork the same day, and at 8:30 AM the next morning, I received an email from the closing agent that they'd already sent the contract to ROFR -- three days at one broker, overnight with another.
So that tells me that some brokers are going to have minor lags at each step of the process, but I don't think any of that should really cause anyone any alarm.
To those waiting, I would say if you haven't had any problems with the buyer or seller in the early stages, relax as much as you can and just wait for the process to play out. I know it's nerve-wracking, but it will work out and you'll be making your first reservation soon.
Good luck to everyone in the process!