The following was first posted as a comment on someone else's blog, but the topic really interested me, so I'd like to continue my internal discussion without cluttering up that person's blog.
Here is the post I responded to. It's really quite insightful.
I think that the holidays we (pagans) place on certain days of the year were probably not originally relegated to those certain days. I mean, I would bet that the ancient peoples who practiced the spiritualities we base modern paganism on, probably celebrated the seasons in the way you described. For example, I bet Imbolc was celebrated as the first ewes began to show signs of milk, not on February 2nd.
In the euro-pagan community (I'm referring to pagans who base their beliefs on European ancestry/traditions), we talk a lot about how Christianity usurped our holidays. Yet, for our 'wheel of the year,' we use specific dates on the Julian calendar, which is Roman and was arguably propagated by the Christian church way back when. Granted, this is like comparing a genocidal massacre to a single natural death, but the point is that we are in fact trying to base a natural rhythm on an unnatural time table. And, we probably have simply not yet moved back to a time when we can collectively celebrate a season without setting a specific date.
This touches on your point about holidays being greater with numbers. With the globalization of human culture, we often would like to celebrate things simultaneously with our loved ones, who might very well be on the other side of the planet, and thus not experiencing the same seasonal changes that we are (hello, Beltane and Samhain on the same day). But we want to celebrate together, so we pick a day that's close. Thus we have the wheel of the year, with specific dates.
Personally, I think the connection between following a Shamanic path and wanting to avoid an unnatural correlation between the actual seasons and a synthetic calendar is both obvious and in practice, healthy.
(Ok, I admit to fixing a typo, but otherwise the above is my comment, exactly.)
As somebody who is wandering down a vaguely heathen, somewhat shamanistic, mostly-led-by-visceral-input sort of path, and who is a member of a mostly-Wiccan coven, I could totally relate to the original post. If it's snowing on Ostara, it's not going to feel like Ostara. But, living in southern Arizona, I actually do get a relatively high level of synchronicity between the calendar and the actual wheel of the year (just don't expect snow on Yule). This year, the first buds of my flowers actually bloomed the morning of Imbolc. On Ostara, my whole town was washed in color by the blooms, and we had a beautiful spring day - immediately preceded by several very cold days.
I do celebrate the wheel of the year with my coven. But, I also have some personal holidays: the first day of monsoon season; my anniversary with Archer; and some of the other secular holidays, like Mother's Day, Father's Day, Valentine's Day, and Christmas - which I don't actually celebrate, but it's "Santa's Day" for my child. I also observe a Day of Remembrance for my cat Naanaa (pronounced "Nah-nah"), who passed away suddenly and tragically two years ago, on 21 March (making the days surrounding every following Ostara somewhat bitter; I'm trying very hard to turn it into a day to honor Naanaa, rather than just a day of grief and guilt... I'll tell his story in another post).
Mostly, I'm content to celebrate some of my holidays alone - certainly Naanaa's Day is better without a crowd, and the first day of the monsoon I celebrate mostly just by dancing in the rain like a crazy person and being in a very pleasant mood all day. Monsoon season is also my favorite time to go walking at night. The nights are still, with the faintest breeze, just cool enough to be comfortable, and everywhere there's green and flowers and wet life. We don't get that the rest of the year, here. Of course, by the end of monsoon season, I'm ready for that dry Sonoran air to come back. Humidity is my fair weather friend.
Of course the secular holidays are easy to celebrate with a crowd - every shopping center in this country gets all decked out, past the point of aggrevation. Maybe when my child's old enough to honor Naanaa with me I'll have some company for that, but I honestly can't imagine having anyone else there, except perhaps the dear friend who first gave me that cheeky little kitten. Nobody else was there when Naanaa died, just me.
It's time to end this post. Otherwise, I'll end up telling Naanaa's story here, instead of talking about calendars. And Naanaa deserves to have his story stand alone.