i've noticed that the saturation table by default is same or at least very similar to the
> perceptual table and the results after conversion with e.g. photoshop are almost equal. > the relative colormetric rendering intent shows very little difference as well.
Unless you specify a source gamut (-S), there will be no separate perceptual or saturation intent tables (they will use the colorimetric table). You can see this if you use iccdump, and notice that the offset for the three tags to the tagtype is the same.
See <http://www.argyllcms.com/doc/profile.html#S> and <http://www.argyllcms.com/doc/Scenarios.html#PP5>.