What damages the filter is pressure, not flow per se. If the pressure IN the tank, or ACROSS the grids gets to be too high, you will likely damage the filter. This is much, much more likely to be an issue if the filter is dirty than if it's clean.

Within the piping, very high flow can lead to air hammer and/or hydraulic shock especially if air is present. These events will break plastic piping and valves. I once saw someone shatter a 6" S-80 PVC pipe that was connected to the pool's main drain, and was 6 feet below water level. THAT was impressive. I had to wade through 2 feet of flowing water to get to a valve that would shut off the flow.

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