ok, thanks for the answer (i hopped it was number 4)...
but i still think that in group chances are higher, for example (i have to explain by steps my theory to explain better):
1ºRule - With a group of six players everyone is weaponsmither;
2ºRule - There will be a certain chance of dropping a recipe for a weapon to each of the member;
3ºRule - Everyone on the group can see whats inside a drop chest/crate/bag
4 - Now here's my theory -> If in a certain a drop chest/crate/bag only one of the members had "positive" (got lucky) chance to obtain a recipe, everyone will have the right to need/greed/pass; a few drops later another different member has its "positive" chance and all members in the group will have again a chance to obtain it by need/greed/pass system, etc;
this means that i can get two or more recipes when drop chances are low for my character and high for a another group member....
Conclusion: mathematically (the formula for drop rate that funcom uses in the game) its always the same but, in reality, chances get "higher" when on group with more than one element having the same skill...
I should also say that one time, when on group, i got a chance to obtain a gemcutter recipe, and this happened because someone on the group was a gemcutter, and since on group everyone shares the loot by need/greed/pass system i got the chance to get a recipe i could not use

....
I think my theory is solid, what do you think?
PutchPT
P.S.: one other question
i was an alchemist at low level character and then i changed to weaponsmith, and at that time i found a recipe and learned the crafting of "Woodcutting: Ashen Walking Stick" and after changing to weaponsmith i did not loose that craft.
so my question is: do i loose the ability to craft the armor/weapon that i found or do i only loose the basic armor/weapon crafting learned from trainers?