I having a dual feelings about this update.

>From one side, putting a small default timeout, motivates a tests
author to write tests which run fast
(so, you can expect to get a test results during your lifetime).

>From other side, a small timeouts, of course is inappropriate for
tests, which depending heavily on various side effects,
like network latency, CPU power etc.

So, i think , there one thing is missing:
 - ask suite whether its using timeouts for tests or not, i.e.:

 runCase

   self usesTimeouts ifTrue: [
       [[self setUp. self performTest] ensure: [self tearDown]]
               valueWithin: self timeoutForTest seconds
               onTimeout:[TestFailure signal: 'Test timed out'].
   ]
  ifFalse: [  self setUp. self performTest] ensure: [self tearDown]

-- 
Best regards,
Igor Stasenko AKA sig.