Is it ok to change:

if (document.images)

to:

if (document.getElementById)

in a simple script JUST for the purpose of disabling the script for Netscape 4?

The script actually works in Netscape 4, and that's why it originally uses
if (document.images)
but there's one part in my implementation that breaks in Netscape 4, and disabling it is fine, as it just displays an image instead of a slide show.

I realize this might not be the ultimate purpose of this code, but it works for this.
I got this from the tutorial here:
http://javascriptkit.com/javatutors/objdetect3.shtml

I just wanted to check if there's any repercussions unknown to me from simply changing - if (document.images) to - if (document.getElementById).

I realize this will also disable it in IE 4, and that is fine.