Oh I think I get what you are saying (I hope). Are you asking whether someone can post something hoping to get an exact timestamp? If so, the answer is Q has done it several times in the past. I imagine it would take some testing to see how long your client takes (app or browser), and to also see how far your phone/computer time is off from the official Twitter/Truth time. It shouldn't be too hard once you have that info, as long as you can trust the time on your phone/pc.

If it were me I would compare times with Twitter/Truth and an atomic clock since computer times can drift. As an example, there are actually some systems that run critical infrastructure that will crash if the time is off by more than a minute or two (depending on the vendor). They usually end up having an atomic time server installed int hose networks.

Even with all that testing I'm sure you could still end up with an Internet slowdown somewhere.