S!
In regards to aircraft mods:
Almost all airforces used waxes, sanding and smoothing of the airframe to decrease wind resistance and increase speed and acceleration.
Any pilot who was successful, who brought back his aircraft intact, without damage then gave his crew chief and crew the time to play with modifications.
These were the guys who got the extras.
The Greenhorns who arrived home in a shotup wreck, were lucky to get it fixed to 100% for the next day's mission, let alone getting it tweaked.
