I think the "information advantage" you speak of is only pertinent if one is managing relatively large amounts of capital -- where even taking a meaningful position would have an impact on the market itself. Extensive research resources, informational contacts, and the general desire for others to provide "useful" knowledge in an attempt to curry favor from anyone running such large numbers, all this is part of a different game that will remain alien for 99.9% of ET readers.
For the individual discretionary trader however, I don't see how one would need to add/develop "informational advantages" to remain successful in the long run. The whole point of discretionary trading to me is adaptation, in every sense of the word, so if one can achieve success with nothing but a quote screen now, there should be no reason why he or she would suddenly need other "advantages" years out.
