I'm not sure. But when I have a think about it, it makes sense that it would be similar. First, in self test mode the computer leaves all settings at a base mark. Second, the way the ISC works, it needs to be able to raise and lower the idle to be able to fully control the idle speed. If you set the idle without the feeler guage then the ISC could only raise the idle. But then again maybe the computer in the EA's is not setup to control the idle, but to mearly raise the idle when under load, ie Air Con, etc.
Hey it can't hurt to try it with the feeler guage, just to see what happens. You never know, you may get a better idle......or your car may not start....50-50 chance I guess, but if you remember how many turn it took for the idle to be adjusted, it'll only take a few mins to get it back to how it was. I say try it, you've nothing to lose!