I believe what the post is originally about is adding images in post in an order to illustrate some sort of instruction. Now the attachment manager allows for images to be reduced at the bottom of the post and allows for someone to view the image slide show per say but not allow the actual images throughout the entire post.
Yes you may use the Image tag but only, perhaps 5%, or a few may have access to web space somewhere but many of these image hosting communities now charge $399.00 USD for off site hot linking. In the past images added into posts could be uploaded to the server but since the change there is now no options or abilities to use both, either, or none for image hosting since the change.
His entire point is that the ability to upload a picture in the post without using the shadow box slide show setup has no options and he and others would like to have that option over being trapped into using only the one way.
