It depends on your notion on style and/or technique (there is a thread). AT got a totally different body concept than Son or Salsa has. BR started to subsume 10 dances under 3 techniques. So in the end it isn´t easy to answer this question.
In my experience it is perfectly possible to teach fusion technique to beginners, but people who learn only fusion dance tend end up in a somewhat infertile dead end. I like the term opendoor intruduced "body concept" - basically every dance has a more or less coherent body concept, and this creates a framework of techniques and "things", and once one has a understanding of that body concept it is possible to extrapolate from it, and to play with it, and so on. If you start with a base that is more varied in its underlying mechanics it becomes difficult to expand from there. Now, there are approaches to fusion that have created their own, coherent body concepts, and those work just fine as a foundation for personal expression of that style.
For me the rule of thumb when looking at fusion dance styles is if they have a interesting third generation. There is always a first generation, but they are usually firmly grounded in one or more original styles. There is also most of the time a second generation - brilliant people who were taught by the first generation and make it really shine. The third generation is the interesting one - they got taught be people who have no experience with the original styles, and the body concepts that make them work, and they have to rely on the body concepts as expressed in the fusion style. And then you often see that the fusion does not quite work without the original foundation.
(it is usually also the third generation that has a "back to the roots" movement, where they start researching the most archaic form of the styles the first generation based their thing on)
Thanks for the reply Gssh! It's interesting how what matters isn't whether the style taught adheres to the basics of the original dances, but whether the teacher knows what (s)he's talking about & is qualified to teach. From my experience the blues-based fusion dancers aren't the most talented dancers due to lack of propers lessons they can take (in either blues or fusion, much less so than in latin) and I could see that depending on who teaches it could be detrimental to the growth of new dancers.
I generally teach the original dances first and give some inspirations later as to how they may extrapolate certain moves or techniques for fusion. Do you have any advice in terms of how to go about teaching fusion directly?