I'm going to presume you also by that imply "read all the standard texts, seminal papers, and current state of the art papers".
Also, it's my impression that start of the art papers aren't really necessary to start off with. The implementation errors people make in their code are flaws that have long been published, sometimes for decades.
Best advice: do deep research on TLS. For every feature, do a directed search of the literature and do experimentation to try to figure out why that feature is there. Most of the features in TLS exist as a countermeasure to some attack. Follow this tack all the way down the stack, starting with the high-level protocol features and working your way all the way down through the block cipher modes and configuration that it uses.