I like teching instead of scoring? It's less likely to be shared?
Though I'm curious as to what the average rate of success is with Metalworking.
I guess I may be biased as I read
this post kind of early on before I am too familiar with the game. However, I do generally share the feeling that getting in age 2 alone early does not give the player significant advantage. One interesting thing that can be said is that if I have Masonry and Writing in hand then I will definitely meld Masonry instead of Writing as I do not want to let my opponent alone in age 1 with the possibility that he can metalwork. So in a sense I even prefer "sharing that metalwork" to writing. From this perspective it seems weird to meld writing instead when I have metalworking myself. But yeah, counter-intuitively it probably is slightly better to meld writing when you have metalworking in hand just because you don't need to worry your opponent will use it.
But let's think about writing itself a bit. How good is it to jumpstart at age two?
So what are the cards in age 2? I would say
generally powerful: Fermenting, Mathematics, Calendar
useful in certain positions: Road building, Monotheism, Construction, Canal building
Scoring: Map making, Currency, Philosophy
So, when you start writing without any score, calendar, construction, canal building, map making, and currency are not that useful even if you draw them. Monotheism can be useful but your opponent is more likely to overwhelm you in the castle department. Fermenting just do not have enough leaves support from age 2 alone and your opponent can easily share it by having his otherwise useless pottery or agriculture on board. Furthermore, you just missed all the "efficiency cards" in age 1, which is probably useful early on just to build a symbol advantage by putting more cards on the table. Except drawing into mathematics immediately, I do not see a particularly good development after opening writing.
And for metalworking, well it is not so sweet when your opponent can share it, but at least in half of those cases you got to share your opponent's Wheels or Mysticism as well.
Oh, and one more thing is that Writing start with 'W' which is horrible. In lots of cases you will end up putting your metalworking on board just to defend a bit on the castle front. Why not get that extra tick by melding metalworking first, when your opponent starts with some power cards such as the Wheel or Sailing? (Okay, maybe if you want to start writing you actually do not want to share the wheel? I don't know.)