connection protection (on separate PNR)
 

I understand AA officially protects the connection from other OW carriers on separate tickets- i.e. if the connection fails, AA will offer alternative flight/routing.

Is this a OW facility or simply a manifestation of AA's kindness ?

AA kindness only. Its on the AA web site somewhere. Is not a OW benefit

Edit
Found the link:- AA Oneworld Separate Tickets Policy

connection protection (on separate PNR)
 

I haven't had to use it before... But I image it's especially awesome for positioning flights with avios ;)

For MH if OW flight conn OW flight, MH will do protection to pax if pax mis-conx. However, if pax onward connection with non- OW's airlines. MH will do assistance only. Won't issue F.I.M or reissue ticket to pax.