Is this true? I can't help but feel it is not?
a slur does not connect two or more notes of the same pitch
Kind of makes sense, you may wish to only 'smoothly' play notes that are not of the same pitch, but it could be said that you could want to Slur notes that are of the same pitch, no?
Take this example (last few bars of Elgar's Nimrod, so sorry for the poor qual)
These could easily pass as Slurred because they are over the notes with the stem down and under the notes with the stem up with an exception of the Cello because I think this is overcrowding?
How would he distinguish between a Slur and a Tie here? Or maybe that's the point? You just can't Slur two or more notes of the same pitch - but you may wish to play them this way as if they were Slurred (smoothly, if I wanted a better word :-).
How then would you notate this?
EDIT: Notice the Fermata too on the rest right at the end, that's strange. To prevent the audience from clapping right at the end of the piece, who knows? :-)