When you play your favorite pop songs on piano, don't feel you need to always play them exactly the way they are on the original recording. There's a huge amount of pressure on famous musical artists to produce "hits" and this means that while their recordings may sound great, they may not be an accurate representation of what the artist may in fact want to do creatively. This is one reason why even the most commercial acts sometimes "stretch out" in concert, adding instrumental solos and interludes to their songs. Many pop artists have deep and varied musical backgrounds and don't want to always be limited to the musical confines of top-40 pop expectations.
When you yourself are playing pop songs on piano, you can bring whatever musical influences you like into play. Do you like the blues? Then let that influence your interpretations. Do you have a classical background? Great! Use that to your advantage.
Elton John, as well as countless other pop stars, has given himself the leeway to play their music anyway they want in concert, without feeling like they have to rigidly adhere to the original recordings. (Madonna's like this too, sometimes altering her hits with extremely different tempos and changes of genre.)
Check out the way Elton plays his hit song "Bennie and the Jets" as a solo piano feature. Even behind his singing, he's playing an extraordinary wide range of rhythms, syncopations, and melodic fills. And then during the instrumental interlude, he simply plays whatever he likes, even Glenn Miller's swing-era classic "In The Mood!"
We can do the same on any song we like. Have fun with your music, and let your own musical influences and tastes shine through whenever possible. You and your listeners will both benefit!
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