I myself have a few things that I normally always do, one of which is pettying at least once before a shot. This is religious when I am a lower rank depending on what answers I do or for an important shot. The others just mainly deal with achievements, not to help out in any other way. Just to get them done, I always complete each petty achievement before I proceed to starting on the next petty. That's just my OCD though. Some myths I've heard are truly absurd though and I really just think someone somewhere down the line just told someone, hey do this and you will get this in return or this boost in this stat and somehow it stuck but it was for laughs. 

If you don't remove someone who hasn't accepted your OC invite, your odds of failing are increased? I'm pretty sure I read that in global chat the other night.

"Barry has a penis."

I hear that's the biggest myth of all.

Yes that's one I still believe Ragnarok, as well as removing people who haven't accepted and leaving your felony timer open. I may be wrong with all three, but limited experimentation has hinted that they may have a factor.

I once remember a very specific time that a CL distracted another CL and made his account inactive for about an hour or so. The thought behind it was that inactive accounts for an hour or so were easier to be killed than active ones. 

Oh man those were the times.

People who haven't accepted have no negative impact, they just don't have a positive one.

Having your felony timer open has no impact, other than you wouldn't be free to re-accept if an OC perked (I'm not sure if many even have the OC Perks still running, so a minor concern at this point).

It's also commonly mentioned that an "average" crime skill is used in the calculations, which is also incorrect. It's just the aggregate of petties and felonies between all accepted participants, so you're better off inviting that earner or goomba than just leaving the spot open if you're trying to maximise your odds of success.

This is how these myths take hold though and they'll always continue too. Facts be damned. It's one of the great things about a community like the one on MR :P