I have been wondering how latencies impact algorithmic trading strategies.

How does lower latency translate to increased profit - in dollars per microsecond?

How does having multiple players who are "equally fast" affect the profit?

For example, is everyone buying the 16ms latency link from New York to Chicago to get ahead or just to stay in the game? The competitive
advantage of better than everyone else (if you are one of first customers) - does it decline/disappear when people jump on it?

Is there a rough estimate of how much a guaranteed 2ms advantage  over everyone else would be worth, for example, on NYC-Chicago path?