Google stop word question

Please explain how this works

[threecrans]

In the thread [webmasterworld.com ] it was pointed out that stop words are not properly ignored when they occur in the middle of a phrase. Brett said the following about this behavior:

It will phrase match if the stop word is in the middle of a phrase it matches. If you get the message "common word", then the word isn't in the search.

I hope I can get further clarification. Let me give a tangible (but fake, I have no affiliation with Tampa hotels :) ) example.

Search for the following

1) hotels tampa // gives a set of results
2) hotels in tampa // gives a completely different set of results
3) hotels on tampa // gives the same as #2
4) hotels at tampa // gives the same as #2
5) hotels by tampa // gives the same as #2

So here is my question.

First of all, the stop words clearly have some effect (as Brett said), or the results would all be identical to #1. So, if they do have an effect, how do the searches 2-5 all provide the exact same result? I would anticipate that if the stop words are included, that there would be some minor fluctuation in the searches 2-5. Is it just sheer coincidence that all of these pages are equally optimized for "hotels in tampa" and "hotels at tampa"?

I think my confusion may be the result of not properly understanding what "phrase match" means.

[ciml]

It's not coincidence threecrans.

My way of thinking of this is that the stopwords are ignored but the proximity of the other words is now different; they're further apart

In, on, at and by are ignored; but Google still takes into account that the non-stopwords have a word in between.