Actually quite a few Wall Street firms (buy and sell side) use a "two track" title system: Rank Title and Responsibility Title. The latter means what real power the title holder really has.
For example, MD - Global Head of Equities is normally considered much more senior than MD - Japan Economic Rearch.
Rank title such as MD without a senior responsiblity title means nothing.
I knew quite a few senior analyst with MD title who is a individual contributer, also knew Directors with 100M budget and manage 200+ staff.
