The problem: complaints by customers in (mostly far off) rural areas that people calling them have lots of trouble getting through. While I can't go through Telecom Digest archives right now, I'm pretty sure we've discussed this. It's a well known problem in the communciations field.
It seems this is courtesy of that whole issue of payments by the inter-exchange carrier to the final local telco. For various reasons dealing with lack of competition and the best intentions of gov't regulators... in some regions that cost can get pretty high.
Hence, the telcos in the middle, so to speak, not wanting to spend all that money, don't give call transfer/completion very high priority. (Which is a polite way of rephrasing what they're really doing).
I'm not sure how long this has been on the FCC's website as they've been making lots of redesigns, but the main fcc.gov page has a discussion of this problem, along with a link to more details at:
_____________________________________________________ Knowledge may be power, but communications is the key email@example.com [to foil spammers, my address has been double rot-13 encoded]