-The \fBscr_set\fR routine is a combination of \fBscr_restore\fR and
-\fBscr_init\fR. It tells the program that the information in \fIfilename\fR is
-what is currently on the screen, and also what the program wants on the screen.
-This can be thought of as a screen inheritance function.
+Either of the foregoing conditions means that
+.I curses
+cannot assume that the terminal's contents
+match their representation in
+.IR filename "."
+The former is due to terminal features
+(such as \fI\%xterm\fP(1)'s \*(``alternate screen\*('')
+that couple cursor-positioning mode with a local cache of screen
+contents.
+.I curses
+cannot know whether the terminal is displaying from that local cache
+at the time the application calls
+.BR \%scr_init ","
+so it makes a pessimistic assumption that a full redraw is required;
+see subsection \*(``Cursor Motions\*('' of \fB\%terminfo\fP(5).