I've had Plantar Fascitis twice and it's a bastard. Six month recovery the first time, relapse about 18 months later followed by a seven or eight month recovery most recently.
The medical bods don't seem to be able to agree on whether wearing shoes or going barefoot/minimal support is for the best. My takeaway from it is that the arch of the foot probably weakens due to wearing footwear causing the issue, at which time it needs the support. After recovery it's probably a good thing to slowly strengthen the arch by slowly building up the time spent walking around barefoot. Only my interpretation and of course I'm not a doctor.