With cells like the P42A it’s certainly possible.
With a standard charge rating of 4.2A/cell a 4P pack could easily be charged at 16A and that cell’s 8.4A rapid charge rating means up to 32A charging is possible without exceeding any ratings (as long as the cells stay below, IIRC, 45°C).
Of course, 8.4A/cell charging would shorten cycle life some. I don’t know by how much.
Is anyone charging at levels a lot higher than 10A?
Are you using a single high power supply/charger or paralleling supplies?