Increasing process variations and sensitivity to operating conditions are making the design of traditional synchronous circuits a challenging task. Correct operation of these circuits relies on timing margins, which have an undesirably high cost in performance and power. One approach to mitigate this cost that is gaining substantial interest is the use of timing resilient microarchitectures that utilize error detecting sequential circuits. We evaluate the sensitivity of the transition detector with time borrowing error detecting latch to timing violations, including violations caused by glitches. Results show that the classic design is more constrained than previously believed and does not guarantee safe operation, i.e. does not guarantee that all timing violations will be captured. To overcome this limitation, we propose transistor level optimizations that enable safe operation, guaranteeing that all timing violations are captured, for a cost of 3 extra transistors, 30% in leakage power and 8% in energy.