No, as a general rule, I don't think its a good idea to work as a bedside RN once you are an APN. Per attorneys I've talked to, you are held to the highest knowledge base no matter what license you work with.
So, even though I'm a CNS, I also volunteer as a pre-hospital RN on my rural fire dept. Every call I go on, I know that I'm held to the standard of care of an APN, though my license is that of an RN.
I went to a call recently where there was an elderly lady who had a ground level fall. All she wanted wanted was a lift assist. As I'm getting her vitals, I casually asked what kind of meds she was on. She was on warfarin, ASA, Plavix plus a boatload of other meds including a beta blocker. Her apical heartrate was 46 bpm. So, as an APN, I should know that she is at risk for a bleed as well as syncope due to postural hypotension. Even though my fellow fire-fighters were okay with doing a refusal and climbing back in the truck, I was insistent that we have her transported as the risk of further injury or possible current injury was too high.