@code{scroll-up-aggressively} and @code{scroll-down-aggressively}.
The value of @code{scroll-up-aggressively} should be either
@code{nil}, or a fraction @var{f} between 0 and 1. A fraction
-specifies where on the screen to put point when scrolling upward: when
-a window scrolls up because point is above the window start, the new
+specifies where on the screen to put point when scrolling upward,
+i.e.@: when point moves forward in the buffer, and therefore text
+scrolls up in the window. When point goes off the window end, the new
start position is chosen to put point @var{f} parts of the window
-height from the top. Thus, larger @var{f} means more aggressive
-scrolling. The default value, @code{nil}, is equivalent to 0.5.
+height from the bottom. Thus, larger @var{f} means more aggressive
+scrolling: more new text is brought into view. The default value,
+@code{nil}, is equivalent to 0.5.
Likewise, @code{scroll-down-aggressively} is used for scrolling
-down. The value specifies how far point should be placed from the
-bottom of the window; thus, as with @code{scroll-up-aggressively}, a
-larger value is more aggressive.
+down, i.e.@: moving point back in the buffer. The value specifies how
+far point should be placed from the top of the window; thus, as with
+@code{scroll-up-aggressively}, a larger value is more aggressive.
These two variables are ignored if either @code{scroll-step} or
@code{scroll-conservatively} are set to a non-zero value.