Originally Posted by
Robt760
And I would go so far as to say if you have a card, presenting it at a TSA Pre-check line will not increase your chance of getting through the expedited line.
I use that card at TSA Pre checkpoints as it shows eligibility for TSA Pre. For the three TSA Pre checkpoints I have used it at, they've never questioned it in the least, and I figure they would generally know about it (specifically the TSA Pre agents, as they are more likely to encounter them than normal agents).