When is a Phrase Mark Not a Phrase Mark?

Few articulation markings are as confusing as the slur.  We are told that it indicates a phrase.  How can that be true when the mark is used in so many different ways?

Aren't there different kinds of phrases, or different levels of phrase?  A melodic phrase exerts its power with or without the articulations specified by slurs: we feel the tension of one tone leading to the next whether or not it goes there directly.  Then, too, there are clearly phrases that are interrupted, by rests, for example.  Mozart seems to have had a special fondness for these, as many of his rests are preceded and followed by the same pitch.

I have come to interpret slurs in the early days of piano composition (Beethoven, Schubert) as pedal indications.  Try it; you may be surprised at what you unearth.  If a single slur extends over what look like changes of harmony it might mean that the chords need to be voiced so as to resonate sympathetically under a single pedal.

I know it sounds radical as a proposition.  The amazing thing is that it doesn't actually sound radical on the piano; it just requires an adjustment in favor of the ear over visual analysis.

Isn't it stunning that the first movement of what we call the "Moonlight Sonata" indicates that the whole movement is to be played "senza sordini" (without dampers, i.e., with the damper pedal down) and that there are very few slurs?  This seems to me a clear indication that the melody is in the bass whole notes and that the famous boring triplets are enhancing overtones of the moving bass line.

Try it.  You have nothing to lose but your probably not-previously-acknowledged boredom.