Amongst swimming teachers, there is a common frustration when we receive children who have been introduced to the water at a young age by swim schools who practise lots of submersions. They are often undeniably confident under the water, but they generally have an unusual swimming technique - where we aim to get our swimmers streamlined and stretched out, these little under water pros are often scrunched up in the water, with an amphibian-style kick.
It can take a good term or so to get their bodies in a good, flat, effective position so that they can learn a proper front crawl and backstroke - they have to relearn a few years of poor technique to get them back to the right starting point.
It is possible to teach a good swimming technique alongside under water swimming - it doesn't have to be a case of either/or. Often, baby swimming specialists train following taking their own babies to the pool for classes - and it's great that they feel inspired to begin a new career! But a swimming teacher who has taught a range of ages and abilities, and who has a swimming background, knows where the baby needs to be in the long term with their technique - they can encourage floats, push and glides and supported swims in the right body position to build a streamlined swimmer for the future.
Going under the water is definitely a valuable part of swimming, but it's not the only thing worth teaching - if we want to create swimmers, rather than submarines, we need to introduce technique from the very start.