Methods and apparatuses to automatically modify a circuit design according to the possible deviation in the subsequent implementation of the circuit. In one aspect, a method to design a circuit includes: determining whether a design constraint is likely to be violated during a subsequent routing implementation of a design of the circuit; and, modifying the design of the circuit to reduce likelihood of the design constraint being violated during a subsequent implementation. For example, a route for a net with a number of fanout larger than two and on a timing critical or near-critical path may be considered sensitive to route topology such that an alternative routing path may lead to a violation in timing constraint; to reduce the possibility of a timing problem in a subsequent routing solution, a transformation can be selectively applied to the circuit design to an extent not worsening a cost function.