Mercedes is wary of a counterpunch from its rivals when F1 pre-season testing resumes in Bahrain next month.
The eight-time consecutive constructors' champions emerged on top in the first three-day test at Barcelona's Circuit de Catalunya, with Lewis Hamilton spearheading a one-two at the top of the timesheet with new team-mate George Russell.
The caveat is no team will have shown its hand over the three days, and the rate of development will be rapid between now and the next test in Bahrain that commences on March 10.
Trackside engineering director Andrew Shovlin said: "We're pleased with how the week has gone.
"We planned a very busy programme for the three days and we managed to get through the high priority items, making good progress with the car and power unit.
"It has taken a huge effort from the team in Brackley and Brixworth to bring the W13 to the track so it's very satisfying for everyone to see it cover 1800 kilometres without significant issues, and to show good promise from a pace point of view.
"We've learnt a huge amount over the last few days and still have a lot of data to go through ahead of Bahrain.
"The rate of progression is going to be very high for all teams and whilst we look to be in a good place, we need to be mindful our competitors may have a lot of performance to come between now and the first race."
Hamilton and Russell head to Mercedes simulator
After completing the Friday morning running at the end of which Russell finished quickest before being usurped by Hamilton late in the afternoon, the young Briton headed straight back to Brackley for simulator running.
Hamilton will do likewise "over the next few days", according to Shovlin who added: "We've still got work to do tuning the balance both for single lap and long run.
"Bahrain is a very different circuit to a cold Barcelona but hopefully we can make good progress in those areas and build on what has been a promising start to our winter testing programme."
Russell, meanwhile, described the testing in Barcelona as "intriguing" and does not believe the times produced "are very representative at all".
Russell explained: "We were top of the timesheets on the C5 compound which is incredibly strong around Barcelona, but I wouldn't read much into it.
"The Ferrari and McLaren look strong and I think we've got lots of improvements to make, we're not fully happy with the balance of the car and the other limitations we have currently.
"But it is only testing, we're here to learn and we have made some important experiments this week and have a good idea of the direction we need to go in."