The in-season development is both a blessing and a curse for Formula One teams.
The introduction of in-season power unit development in 2015 will create an extra headache for both the teams and the manufacturers, some of the sport's key players admit.
In 2015 the manufacturers will be allowed to use up engine development tokens during the season, rather than before the season, as had been the FIA's original intention.
Last year was already a little bit of a headache, it's just going to be more complicated.
The problem they now face is the timing of the introduction of any updated parts, as it has to be done with an eye on how much mileage the previous examples have done.
Last year, when there was no development other than for reliability purposes, teams would not have had a problem using elements at the last race that had been in circulation as early as Melbourne, as long as they still had mileage on them.
Now they risk a dip in performance if they are forced to go back to earlier parts. While mileage on older equipment could be used up on Fridays, juggling the elements around still presents a challenge, especially now drivers only have access to four power units before penalties kick in.
Cause and effect
“If you do use tokens up through the year then the introduction of that will mean what you had previously, you won't want to use,” said Mercedes engine head Andy Cowell when asked by Motorsport.com.
“Which does complicate it. That's one of the things to consider as you come up with ideas and decide what you want to do.”
Meanwhile McLaren's Eric Boullier said: “Last year was already a little bit of a headache, it's just going to be more complicated. It's true that four engines, with an upgraded package in the middle, we have to be very cautious how we manage our laps, especially on Fridays.”