In interpreting deal documents, an issue arose as to the definition of the word “control” when used in an attempt to obtain “control” over a board of directors. For that reason, and others, the law firm that drafted those documents was found liable to its client to the tune of $17.2 million. The details are a bit complex, but worth a read. Have a look here. Read the comments too.
Bottom line: Write what you mean. As simply as possible.