For a typical BPLer, the Intro to Snow Camping would feel a bit slow, because most of the participants won't have as much backpacking experience and most won't be lightweight. However, to be fair, the info is good, it's a safe environment in which to learn and the more advanced leaders, some of whom are lightweight or ultralight, will be happy to share more advanced info and tips. The winter backpacking/backcountry skiing book you read in the course is the same book recommended by many on BPL and illustrated by BPL's Mike Clelland.
Alumni trips you can do anytime after the intro course or equivalent experience are no different than the planned BPL Bay Area winter outings – just for fun or learning a new technique like traveling with a pulk or a particular destination like Yosemite. Tony Wong did a Yosemite trip with them last year to a very nice spot and posted photos here.
For winter backpacking trips, the SF Sierra Club chapter has much more going on than the Palo Alto chapter. It runs a large, well organized program with many different beginner and alumni trips. Both chapters have good backcountry skiing groups with regular backpacking and backcountry cabin trips, though I don't know the SF backcountry ski group.
In general we find with the Sierra Club chapters you have to get to know which groups within the chapters are best for your type of trips and then find the ones that are a good fit people-wise.
Just for example, the Day Hiking group from the Loma Prieta Chapter does epic day hikes with sick mileage and elevation gain. Many would be hard pressed to keep up with some of the super fit older hikers in that group. Not what you would have expected based on the name.
Note that I think Ned's program sounds like a nice complement to the SC course and well worth it and he sounds like an interesting person to meet.