Most mongers don't repeat past the first session if they deemed the session to be even average, much less if it was weak.
So a review after the first session would capture the initial assessment, which is something helpful to others who also will see a girl for the first time. Most people read reviews of girls who they've yet to see.
I also do find that in more cases than not, further sessions improve experience. However, something to understand is again, a monger who didn't have a great session is unlikely to repeat again. There were a few girls I liked who required some time to gel or a specific approach. The only reason I've stuck with them is because they offered good service regardless. Most mongers aren't as patient. So when I review a girl I've seen a few times and who requires several sessions to warm up, I always warn others. And out of those people, maybe 5% actually went on to see the girl. Many people want instant gratification in this biz, not play games they can play at a bar.
Most people don't want to spend a G on mediocre sessions in order to potentially improve them by thee fifth session. They'd just rather spend that $ on three good sessions. And I can't blame them.
So overall - I'd say even if you seen a girl a ton, I'd cater and tailor my review as per first session. I'd obviously would say that I've had many sessions, and clarify what things might open up, but I'd keep the review as what you'd expect on a first session. As to not set expectations that are unreachable on the first date.