Yeah, Susan, I often use the chords that are printed in the songbook or sheet music as a jumping off point for MY chord pattern--one that fits my capabilities, harmonies, etc.
Occasionally I will be 'stumped' on a song because I can't figure out where the chord pattern STARTS (if it starts off with the 5th or an unusual chord). Once I get my bearings, e.g., from a chord sheet, the rest comes naturally. And if the sheet music puts in what I think are unnecessary chords, I often omit them. If it leaves out chords that would add richness or pizazz, I may add them.
There's another nice thing about lyric sheets printed with chords -- you can share them, withouth having to type everything out yourself and add chords. (I have tons of songs that I know how to play but for which I end up spending time generating lyric/chord sheets for jams or song circles--reinventing the wheel, as it were. That's why a book like "Rise Up Singing" is helpful in settings like that.)
Genie