Not that I think they’d do it, but Jim Miller advocating keeping Justin AND drafting Caleb. Thinks it's viable. References Brees/Rivers. Says he's a big Justin fan and he has all the ability you would want but had some well reasoned criticism of him, too. Doesn't like that Caleb skipped the physical. Said he probably "turned off the Bears and 31 other teams"
I do think if getting the QB position right is the priority (and it probably should be) having both is viable. Would take some massaging of egos for sure.