The charge that post-tribbers view the Lord as "long in coming" is not logical. "Long in coming" is not about imminence, but about losing patience and losing faithfulness.
If the master is away, and says "I will send a messenger ahead of me a few hours before my return", and ten years goes by, the imminence never changes, and whether or not people believe in the signs before His Coming does not change their level of Faith or patience.
There is no connective logic for claiming post tribbers are the "unfaithful servants". It doesn't make sense.
If you are watching for the signs, then you are remaining watchful. If you believe no signs will be given, then you are not watching for them. Think about it.
I'm not saying post trib is definitively correct, or that pre trib is false, but that neither view is critical enough to the Gospel to make salvation judgements based on a person's understanding of the Word.