I've been making a habit recently of picking up on an old technique for keeping myself sharp: pick one prime lens, at random [set them on the floor, spin a beer-bottle, pick up the one that 'wins'] and shooting with it exclusively for a day or two. Sometimes I do it for a week.
The 300mm f/4 can be a bit of a challenge but actually no more so than any of the other primes, to be honest.
Like how this one came out. Shot the other day in Shibuya whilst waiting for the lift to take me, the wife, baby Charlie and his pushchair down off of the overpass near the South Exit of the station.
Custom picture control: Monochrome HC01
Nikkor 300mm f/4 ED