I wouldn't have minded learning the effects of this lens had I liked the rendering of the effects. That rendering is important to me but I certainly don't expect others to share my own preferences on the matter. By the same token, I had visualized an effect, and the lens didn't match my visualization.
Sounds very familiar, from seeing images made with this lens (and liking the effect) I had an assumption what the SF effect is supposed to look like so I went and shot lots of pictures. There was not a single keeper among them. Reason: the situation I used the lens was different and SF didn't make sense in those situations I used the lens in, so my pictures were pointless. By far not every situation warrants SF at all. It took me a while to understand what the effect does and what a motive must look like to make SF a useful effect.
By this I don't mean "shoot a candle and get that glow"-pictures, those wear off pretty quickly after a few pics. No, it was: what does the background and the main subject have to look like that SF produces this beautiful oily coloration and what was even more important: when would this oily coloration actually enhance an image instead of just making it look like a poor OOF shot?
That is an easier position to defend artistically, it seems to me, than spending a considerable amount of time learning a lens just because one should be willing to learn. I have lots of lenses that teach me lots of things, but in the end they must serve my visualization, not dictate it.
Soft focus requires very different composition from other shooting styles, since the foreground motive which your eyes would normally lock on, is blurred. Most of the time blurred areas in the foreground just make my eyes hurt and are not all that attractive. One has to figure out which motives lend themselves to being blurry in the foreground and still yield interesting and pleasing pictures. You suddenly have to think of your foreground motive as an arrangement of areas and colors - not lines or patterns.
IMHO the 135SF turned from a classic portrait lens (which the cliched look) into an artistic lens with a lot of potential. You could compare it to the lens babies, which also have artistic potential but a nasty learning curve. But it's obviously up to anyone by himself to decide whether that is something one wants to pursue or not.
