Whar I mean is this. Myt partner has been playing piano for thirty years, she can read anything well first time, she cant improvise a note. This is the way I was taught 'classical' method, on my first instrument. I really wanted to improvise, could read anything but was stuck - completely stuck.
The modern musician almost must improvise. Many of the bands I have been in have very accomplished musicians that cant read a note - particularly gu8itarists. Why? Well notation just cant capture certain things, the wail of a blues harmonica or the screech of a electric solo - how can you write these things down? If you do it would be so complex that it would only be readable by the very few. I once was handed a chart of a sax solo it was full of demisemiquavers, but all that was really happening was the player was coming in a little early.

Whilst I agree reading music in an elementary way is useful and should be in the kit bag, I have on my bookshelf several volumes of piano exercises, for impro and tech, I would not suggest putting these in front of the eyes and playing them. Much better (IMHO) to dispense with the third man (the page) and just have you and the piano. Learn some theory, learn some song forms, then apply your exercise to these. not to the original exercise only, but also to other settings, this way learning increases exponentially
My partner can easily read the heads of the Real Book but flounders on the chords.
Its just a personal belief, but I feel that harmonic understanding should be taught first, and applied rigorously, before reading, reading has its place of course, but even the accomplished classical player dispenses with it as soon as is possible. When I read for the piano I make sure to close the page as soon as I have mastered a phrase/line that way I memorise. Its a common trap to use reading as a crutch. Who wants to walk on crutches?

Just a point of view...

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