[plt-scheme] ->d Performance

[Robby Findler]

Popping out one level, this kind of use of contracts (roughly: on
field accessors) is one of the places where I know that they can have
a non-trivial impact on the overall running time of an application.
The best suggestion I can make for now is to either use Typed Scheme
or to move the contracts onto higher-level abstractions that get
called less frequently.

Sorry,
Robby