Hi
Sorry you asked and you will get a short ansver without the fumes of
grog ;
The oakum are forced in loops between the planks so it stuff the gab
from side to side not bottom up , for that you need 15 different types
of caulking iron and made right the caulking can not be pulled out,
--- it easily can if an amature done the job one that don't have the
feel only heard about it, the tar is there not to make anything water
tight, only to keep the caulking in place.
Caulking is realy an art a great skill , you would know that in a
wooden boat.