Jon has proven many times he can successfully write without Richie. And, having seen the band without Richie, they're just fine live without him too. They're still a great live act without him. Richie is not a "co front man" and never has been (unless you've got on Richie goggles, I suppose). Taking lead on a song here and here does not a co-front-man make. It's throwing the guitarist a bone. They're not a band without a guitarist. They're a band without their original guitarist. Many, many bands have a revolving door of members. Better a new guitarist than a new singer, IMO, as many of Bon Jovi's peers from back in the day have struggled with.