Montserrat was such a pivotal time, it's not given, nor could it be at the time, much depth on 25X5 as it was barely 7 months before it's release in Dec 89.
With Hindsight Keith's "I'll see you in a few months or i'll be back in week" quip to Patti is monumental, that's how tenuous it was, could they find a way to productively work together again.
IMO This is the time when they either had to "Get On Board the Bus" or go your own way, the Bus being the Business of the Stones. Thank goodness they did, this purely commercial era, with side indulgences and Tie In's (I Love their Marketing chutzpah)