Suggested

The Overcut

David
It's only the opposite of real life because today's F1 rules don't allow refuelling. The undercut works in real F1 because the car on new tyres is roughly the same weight as the car on old tyres meaning the tyres are the determining factor.
The rules in iGP do allow refuelling so the undercut only works if the car that stays out longer takes the tyres well below the minimum wear limit to a point where lap times suffer.

Hi Andrew. You are correct that higher weight usually leads to slower lap times for the first few laps but providing the cars are fast enough to remain in the DRS train without burning all their boost the overcut can be effective.
It also often means that towards the end of the race the team that pulled off the overcut are on fresher/faster tyres.
Of course, there is a limit, in my experience running the cars too long means their tyres are shot so any gain you make by running lighter at the end of the stint is negated by loss of lap time from degraded tyres.
There is usually an optimum strategy and after a couple of seasons in a well attended competitive league almost everyone uses a similar strategy, very rarely is a different strategy successful.