Having learned a few languages with different methodologies, I strongly disagree. The most effective introductory method I've encountered so far is Pimsleur, because of its focus on listening and speaking at the early stages.
I've seen too many students who learn using the traditional theory-heavy approach and who, after years of study, are like deer caught in the headlights when they're confronted with the actual spoken language. They're also often saddled with poor pronunciation forever (which really degrades native speakers' perception of your language proficiency, regardless of how fluent you are).
Some theory is helpful, particularly for languages with lots of grammar (i.e., Indo-European languages with case, gender, agreement, etc.), but like playing an instrument, learning a language is 90% practice.
I've seen too many students who learn using the traditional theory-heavy approach and who, after years of study, are like deer caught in the headlights when they're confronted with the actual spoken language. They're also often saddled with poor pronunciation forever (which really degrades native speakers' perception of your language proficiency, regardless of how fluent you are).
Some theory is helpful, particularly for languages with lots of grammar (i.e., Indo-European languages with case, gender, agreement, etc.), but like playing an instrument, learning a language is 90% practice.