Normally,
Pressure is on front car. 2nd place stays out, you stay out.
You are in front, you will stay in front. If 2nd car goes in, he falls behind.

If 2nd place goes in, you go in......IF IF IF there is enough time left that he would have caught you on fresh tires.

To sucker the first place car into the pits,
2nd place has to make it look convincing and when the first car has committed to go in, 2nd place stays out.
The worst that happens is that the first car slows, and NOW 2nd car stands a good chance of catching first place car.
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And yes, if I can hear them over the radio, the opposition team can also hear.
There is a small lag time from when you can hear it, before you can call it in to your pit.
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