Inside Macintosh: AppleScript Language Guide / Part 3 - Appendixes

Appendix B - Scriptable Text Editor Dictionary / Scriptable Text Editor Commands

Move

The standard Move command is defined on page 106. The Scriptable Text Editor version of the Move command behaves like the standard version,
except that the direct parameter cannot be a list; it must be a reference to a single object.

For example, the following statement results in an error:

tell document "Intro" of app "Scriptable Text Editor"   move words whose style contains bold to beginning
end
--result: error; Move can handle single objects only