Ricky's humour is more obviously awkward, whereas Steve is a bit more depreciating. I sometimes think he should get more credit, but everything seems very mixed up anyway. The Office and Extras are mainly Ricky's PoV in life. Ricky's obviously very intelligent, but it clashes with his humour a lot so I think some people think Smerch is the one who does all the work. Hard to say... We wouldn't ever had anything from them without each other, so I guess that's the strongest thing you can say towards both.
Unless you meant something else by "claims a lot" ? In which case... I think some of that is just human condition, too. If you're talking to someone or a child, it's weirdly more natural to say something to think is plausible than admitting you don't know. (Karl was the child in that scenario).