Norm, if the nail head is like a finishing nail and not very large I
would try to drive it right on through the plank with a fine pointed
punch. It has to be no larger than the nail itself.

But if the head is fairly large, driving them through might split the
teak board. If so, you might try to cut the head off with a carbide
plunging router bit or possible some sort of drummel tool ....and then
drive them through.

Getting the 'holly' separated after the boards are up should be easy if
layed without glue as in the states. If solidly glued in your only
option is probably to cut the out on a table saw, both between the
planks and later out of the grooves.