The French all-rounder started the stage 6th overall, 1:08 down on overall leader Julien Vermote (Etixx Quickstep) but picked up two seconds at the first intermediate sprint before gobbling up three more at the final intermediate sprint.
Five seconds may not seem all-important at this stage but they were enough to move him up the overall two places to fourth and tied for a place on the provisional podium along with Ben Swift.
"I took some bonus seconds but I was just in a good position in the peloton. Then I tried on the climbs but that was just to test the legs and then to try and make the race harder for my sprinter Jens Debusschere," a relaxed Gallopin told Cyclingnews at the end of the stage.
The nature of the Tour of Britain, with the six-man teams, deceptively punishing terrain, and aggressive racing, combine to create an air of unpredictability within the race. The action and the outcomes can flip at any moment, although the uphill finish to Haytor and individual time trial at the weekend appear the most crucial stages remaining for the GC honours.
"I'm not really here for the overall. First it's about winning a stage. I see that I'm in the same time for the GC as some of the riders like Rohan Dennis and Tom Dumoulin, but if I stay like this it will be hard to beat them with the time trial. If I can get 20 seconds on them in GC then it's not to bad but I will do my best. It's going to be hard to beat Cummings and Vermote for the victory."
Vermote currently leads Cummings by six seconds, with Dan Martin in fifth and a threatening placed Tom Dumoulin at 1:12.
"First I'm not sure I can take time," Gallopin said, opening up slightly on the GC battle.
"I saw that Dennis was strong on the second stage and Dumoulin also looks really good. If it stays like this then it's not enough time with the TT so I have to try something. If I can take 10, 20, or 30 seconds that would be really good."
Gallopin, although racing the Tour of Britain this week, has also targeted the European Championships, which take place a week after the British race concludes.
"The selection hasn't been made yet. We have strong guys like Julian Alaphilippe and Samuel Dumoulin but the nine riders are not selected yet. We go there with a strong team though."
"I know the race really well because we have a French Cup there and the finish of the team time trial was there at the Tour last year. It's uphill and 17 laps."