New performance mode boosts Switch handheld mode clocks by 25 per cent

[Faelco]

Tmfwang said:
And halfes the battary time?

It will obviously lower the battery time.

Eurogamer already talked about a boost mode long ago IIRC. But they said back then that it would be to keep the entire docked power for the handheld mode (which would have killed the battery time even faster).