John makes many good points but he has missed one important factor. I'll torture you with some other thoughts before talking about that item.
With regard to safety in numbers I absolutely agree that for all intents and purposes once you leave the dock there is very little value in being part of a rally other than company on the radio and the parties at your destination. There is value in the preparatory seminars and camaraderie. A lot of information is shared there, not just from the presenters but among the participants.
Climate change is unquestionably a factor. Whatever you may think about causality the climate is changing. Herb Hilgenberg and I had a long discussion on this subject almost ten years ago when I was planning my first transatlantic crossing. The real and measurable changes reduces the value of classic Sailing Instructions and pilot charts. Add in the significant changes in boat performance and the historical routes and practices have less relevance than attributed to them. Jimmy Cornell's new Ocean Atlas is one attempt at addressing the change, using modern data collection over a short period of time (years, not decades or centuries) to update the pilot charts. Jimmy and his son are working on a software version to provide the functionality of VPP with the new data set.
John's discussion on windage is important. The "junk on the back" tendency is a huge deal. There is just too much c$@p back there on many cruising boats. Enclosures, solar panels, davits, wind gens, dinghies, grills, jugs, roller furling sails, and other "stuff" have a bigger impact on sailing performance than most cruisers understand. It is huge and completely unaddressed by any of the sailing/racing rules others have promoted as the "answer" to the "rally problem."
Sailors have to have a means of managing their sail plan. Furling headsails have limitations, not the least of which is windage forward as you roll them up. That's one reason I head offshore with a 100% jib on my furler. It has less windage than my 135 when rolled up. I'm a big fan of cutters and cutter rigged sloops and ketches. The staysail greatly improves pointing (and thus options) and keeps the center of effort in close to the mast. I'm less of a fan of trysails and prefer deeply reefed mains but I won't argue with those who feel differently. The point is to get the sail area down while retaining propulsion and control.
In my opinion cruisers should be as self-sufficient as possible. That means understanding how weather works and having the resources to get weather information on the boat. I like weather fax to get synoptics. I've posted before on the shortfalls of gribs. Regardless, I am in the same camp as Lee Chesneau and Evans Starzinger -- you should be your own best forecaster and router. If you choose to use the services of someone else like Chris Parker (who I know, like, and respect highly) you should be having a discussion
with him based on your own observations and not just blindly consuming the guidance of someone else. The weather a router sees looking out the window is not what you see (you are looking out the window, aren't you?). Synoptics, a calibrated barometer (a barograph if you can swing on), and some understanding of meteorology are core to safe passagemaking.
Andy Schell's blatant commercial for the WCC/ARC is just embarrassing. The Caribbean 1500 was down to just 30 boats this year while the Salty Dawg was up to over 130. Anything can certainly be improved, but rallies like the NARC and SDR are clearly attracting more folks than the expensive WCC events. Jimmy Cornell sold the ARC at just the right time. Smart guy. *grin*
The issue that hasn't been addressed is that of the insurance companies policy with regard to named storms and the calendar. The old 1 October date became 1 November. The actuaries decided that another month would reduce the probability of hurricane damage. In exchange those headed South offshore are more likely to hit nasty conditions associated with big frontal passages. Not all of us fit under the bridges on the ICW, and even those who do don't like the journey so much.
I'm not a rally person myself (well, I have spoken at seminars) but I do think they are a perfectly acceptable way to make a passage. When you are at sea you are responsible for your boat, your crew, and yourself. No one else can be responsible for you.