This should be the default behaviour. Keyboard shortcuts should behave predictably. The point of keyboard shortcuts is to make you faster. 

Sublime Text needn't add this feature, but the API should make it possible for a package to provide it.   Right now the API is missing the necessary hooks. See http://nickgravgaard.com/elastictabstops/news/elastic-tabstops-lite/  by Nick, the inventor of elastic tabstops ( and https://github.com/SublimeText/ElasticTabstops/issues/4 )