Yes the smell does dissipate, We were working on a funny car chassis and my welder kept giving me the stink eye, he finally asked, are you wearing some nasty cologne or something? HA! No it's just the stuff I put on the yamaha seat.
I've applied it to the sandfcast's seat 3 times maybe. I don't think it needs any more, it feels like new and no cracks so far. I've used it on a couple more bikes since, it seems to dry in the seam areas first so I reapplied it there.