It should be true from what i know. I put the code i am using up in the post.
When clicked it changes the url to the embed version. All cb affiliate links do that again from what i know.
I do not know what url you are using. The ones I use come from the API so they are slightly different then if you are using the embed url from the promo tools. Should work the same I would think.
Here is a gif that shows the different sizes (as you said you could not get it to do), then the url that is in the source code and then the url you go to when you click in to the iframe.
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