Hi Wild
Where abouts on the deck is it?
Although I haven't tried it, I will have re-deck my mossie or mossies one day. My idea was to get my router and set it to the deck thickness or a bit less (to finish the last mm by hand) and just go nuts, around the gunwales and across where the frames are.
But Bens right a bit of glass would be best, you can keep repairs like that pretty neat without getting into a major job.
The Taipan I've just build has a layer of 85gm woven cloth over the entire deck area, and will/should stop those cracks appearing and it stiffens the whole platform up as well, and adds very little weight.
Regards