Ik want to optimize a page for keywordA keywordB, because it's a phrase many people search for. But my page title and header would make a lot more sense if I'd write it as "keywordA and keywordB". Would the addition of 'and' (or 'or', 'with' , '&', etc.) make any difference for the page's ranking in Google for the query keywordA keywordB?
By default, Google only returns pages that include all of your search terms. There is no need to include "and" between terms. Keep in mind that the order in which the terms are typed will affect the search results. To restrict a search further, just include more terms. For example, to plan a vacation to Hawaii, simply type vacation hawaii. taken from: http://www.google.ca/intl/en/help/basics.html#and
In information retrieval common words as "and", "when", "or" , "in" etc. are sonsidered to be stop words and algorithms suggest that all of those stop words should be substituted with STOP_WORD.
My web pages tend to come up when people are searching for terms with "and" in as Google tends to ignore these words (unless in CAPITAL LETTERS). For example, do a search for: maggots and killing And read what appears under the search box
That is a very good question, probably is the answer. In general it is better to be grammatically correct because humans like it that way However Google can present a different SERP when you use 'and'. For example try the search bread butter and compare it with bread and butter. Interestingly in the AOL data set of 36 Million records there were no searches for bread butter but there were searches for bread and butter pudding, bread and butter pickles, bread and butter pictures, bread and butter pudding etc. - Michael