In our last game session, the players were negotiating with a Trandoshan.....

Seems perfectly reasonable.

Now the question is, how often do you test the players Xenology and other knowledge skills?

I suspect that the reason some people will not see any worth to various skills is that their GM or they themselves don't find a suitable use for the skills.

What if your party were in combat with a Transdoshian would you ask a player to make a Xenology test and adjust their combat based tests?

What if you went to a planet of Transdoshians, are they culturally identical to those you have previously encountered? What if they find the great hunt offensive?

What if you are fighting the renowned Transdoshian General, are you aware he always begins his attacks with a feint down the left flank?

These rolls don't just apply to social situations, nor do they have to be GM led, the player could initiate the dice roll. Which is the beauty of allowing the players to create narrative.

@knasserll: I am sure you know that, I am just using your post to springboard into my thoughts.

In our last game session, the players were negotiating with a Trandoshan.....

Seems perfectly reasonable.

Now the question is, how often do you test the players Xenology and other knowledge skills?

Well we've only done two short adventures so far and both were on the same, human-dominated planet. So an answer to this may not be useful. Off the top of my head, they've rolled Xenology (as discussed), a Core Worlds roll (to determine where someone's accent is from) iirc, there was definitely a Lore roll but I don't remember for what though I remember realizing post-game that I should have used Education. And we had a Underworld roll to find out who the local crime bigwigs were. Anyway, knowledge rolls seem common enough to me.

I suspect that the reason some people will not see any worth to various skills is that their GM or they themselves don't find a suitable use for the skills.

Then in those cases I suspect one of three things is most likely: the GM runs adventures that don't stray too much from a fairly obvious path meaning the players have no need to actively find things out; the GM doesn't bother asking for rolls for knowledge and just gives them it; one or more of the players are very familiar with the Star Wars setting and uses that knowledge whilst the GM also stays within the published setting rather than inventing new races, planets, etc.

I find all of those a negative for varying reasons.

What if your party were in combat with a Transdoshian would you ask a player to make a Xenology test and adjust their combat based tests?

No. They're basically humanoid and their physiology animal. I don't see what special knowledge is required to successfully shoot one. It could be useful in a larger scale violent situation where the players were in a jungle hunting or being hunted by the Trandoshans. Xenology might give you clues as to how the Trandoshans would behave. Though I think that would be more useful to more esoteric creatures. Do rancors hunt in packs or alone? If you're being chased by a rancor male and you head toward another male, will they turn on each other and forget about you? These are useful Xenology rolls for combat scenarios.

What if you went to a planet of Transdoshians, are they culturally identical to those you have previously encountered? What if they find the great hunt offensive?

I'm really not sure what you're getting at with these questions. But it's Star Wars - all Hutts are gangsters, all Correllians charming gamblers and everyone wears a chapeau on the Planet of the Hats.

More seriously, what if they are different? Then the result of knowledge rolls is different. In your case of the Trandoshans who find the Great Hunt offensive, Xenology would still be useful. You're only going to put your foot in it if you already know that "all" Trandoshans love the Great Hunt. A successful Xenology roll would point out to you the marked absence of shrines to the Great Scorekeeper and how uniquely there were no trophies on the wall. Your successful roll has clued you in to there being something very different going on.

I'm really not sure what you're getting at with these questions. But it's Star Wars - all Hutts are gangsters

Oi, spoilers. Now I don't need to buy the Hutt sorcebook, they are all gangsters.

Kinda funny reading back on this thread.

My son is almost a year old, he was born on March 20, 2014 ... I don't know what I was doing getting in a long forum debate on that day! I could have sworn I'd been busy with other stuff