The American had a difficult start to a schedule dominated by unfamiliar venues and tricky street and temporary tracks that saw him involved in a string of incidents as he struggled to keep up with team-mate Alex Albon.
However, in Austria he had a strong run to 13th in a race of low attrition, while at Silverstone he finished 11th and just four seconds behind the Ferrari of Carlos Sainz.
Robson acknowledged that the return to Europe and tracks that Sargeant knows and which have a little more margin for error has been a boost for the youngster.
"I think that makes a difference,” he told Autosport. “And at the same time though, there is just that learning, that experience, good or bad, I think it all is really valuable. So hopefully things are just starting to come together.
“I think the next two will be really interesting. They are circuits he knows, circuits that he should be quite good at.
“The pace of the car will fluctuate a little bit maybe. From a mindset point of view, I think if the pace of the car is off a bit, then that's another good learning experience.
“He's got to keep up with Alex in a race where we're less competitive, which is a slightly different kind of mental state he's got to control and get through.
“Or ideally, if the car is actually just quicker than we think he might be, then he won't have to deal with that. But it's good learning.”
Source: Autosport