The son-and-father crew took their second class win of the year with a dominant drive on the Oban-based event.
Co-driving dad Iain returned to the passenger seat after being forced to miss the last round through illness, and celebrated his return to the hot seat with a win.
Apprentice joiner Sean (19) was setting the class pace right from the start of the rally, showing no fear for the steep drops and big crests that make the Argyll forests so infamous. The result moves the Robson crew up into second place in the Peugeot-only series after four rounds.
"It's good to be back to winning ways again in the 205 after winning the first round back in March," declared Sean Robson.
"It would have been easy to have been fazed by stages with such a scary reputation, but we prepared like we would for any other rally and went out with the mindset that we needed to win - and it seemed to work."
Duns teenager Garry Pearson was plagued with fuel starvation issues for the duration of the rally that slowed his progress. The mechanical problems worsened throughout the day, consigning Garry and Aberdeenshire co-driver Tom Hynd to seventh place in the Peugeot 205 standings.
In the Civic Ecosse Challenge for Honda Civic cars, meanwhile, St Boswells' Ross Hunter narrowly missed out on a second consecutive win.
Hunter and Jedburgh navigator Eildon Hall were pipped to the Honda win by only a second, losing out to Glasgow's Grant Inglis after a spirited fightback over the afternoon stages. Technical problems cost Ross and Eildon time early on, but once the issues were resolved the pair flew through the forests.
"The engine kept cutting out on us and the car wasn't handling right, but our service crew were able to trace both problems and sort them for us," explained Ross (22).
"I feel I'm getting more and more confident with the new car, and after two good results in a row our season seems to be turning a corner."
The next Challenge round will be the Gleaner Oil and Gas Speyside Stages in Elgin on Saturday, August 7.