You are right about that.
One of the most glaring examples of that was Worf's behavior in "The Ship" (DS9). I saw this episode not too long ago, so it's still somewhat fresh in my mind.
Sisko and his landing party took refuge in a downed Jem'Hadar ship. One of the men, Muniz, was seriously wounded. He happened to be one of O'Brien's underlings. Worf and O'Brien almost came to blows because Worf kept insisting that the wounded dude was a goner; that it would be better for O'Brien to put an end to Muniz's suffering because that would be a more honorable death; and that O'Brien was just another weak human afraid of facing death.
Worf showed zero compassion for Muniz. Worf was behaving like a Klingon, even though his behavior may have been obnoxious and insensitive to a human. Worf is what he is. And his culture is what it is.
However at the end of the episode, Worf, all of a sudden, became compassionate. He went to the cargo bay to sit alongside O'Brien, who was keeping Muniz's body (which was in a torpedo casket) company. Worf went against his Klingon instincts and culture. He suddenly "discovered" his humanity instead of being what he is.
On a side note, Worf's explanation for his presence was that there is a Klingon tradition that when a warrior dies, his comrades stay with the body to keep away predators in order to give time for the spirit to go to stovokor. How come we never heard of that tradition before?
Was Worf making up this tradition? Previously, we were told that a Klingon's dead body was nothing but an empty shell that didn't need any further respect paid to it.