Rohit's comment in the previous post prompted this, though I have long debated with myself and others on the topic.
I have written some reviews to have slightly experimented with the art of writing. My initial style was to completely describe the plot, including the smaller details I have noticed, and then intermittently add comments where I had any. This, of course, made reading easier. One could read without seeing the film at all and yet understand more or less everything I said. I abandoned that for chiefly two reasons: first, it took a lot of time to write, and second, it took away some of the reader's joy in discovering the details by himself/herself.
Next, I focussed more on technique (for example, my review of Kurosawa's High and Low commented at length on cinematography and blocking, and included screenshots on which I made comments now and then) while retaining a basic outline of the plot. I was more or less happy with this, except some of my oldest readers told me that they had trouble understanding where I was getting at. To put it more clearly: analysing the script (or story, as some would say) primarily, with little notes of cinematography, editing, music and mise-en-scene maybe, makes a review less cryptic to the general reader.
Now, some of my favourite writers on film take completely different approaches to provoking interest in the reader. For example, Baradwaj Rangan, in his section on foreign films (which is what I've read most on his blog), usually discusses the opening few minutes of the film in detail and leaves the reader to discover the rest for himself (Part of the Picture). This is, I think, a good enough approach though it cannot be applied when one wants to comment on the whole film.
The approach that I have now decided to use for reviewing a film (as opposed to, say, comment on the thematic connections within different films of a director) is one that combines elements of both approaches I spoke of in the second and third para. I write the plot in some detail, at least enough for me to make a few comments on the way characters develop in the course of the film. I leave out the tiny bits than delight me so that the reader can discover them on their own. I really don't want to deny anyone that joy!
I still assume that some people object to spoilers. So I'll briefly question the significance of plot in film. My own take is that, thrillers and mysteries excluded, the knowledge of the events on screen rarely diminishes the experience of watching. (How and why is more important than what.) If anything, it takes our attention off the framework and allows us to notice the details. You could of course complain if I spoil a Hitchcock film, but an S Ray? I don't think so.
P.S. - Specifically on Ray and my review of Kanchenjungha, I have gained confidence that two of the best writers on the director - Andrew Robinson and John H Wood - have followed an approach similar to mine in their books.