[Mullins]

If I've got 1-2 weeks to train for a CW event I need to be spending most of that time doing inhale dives to depth, because that's the only way of experiencing the narcosis, fine-tuning (ok, rough-tuning!) my dive strategy and finding out how deep I can expect to go come competition day. FRC would be helpful longer-term, but it's too different to be useful within this timeframe. It does not properly simulate deep equalising, at least not for me, possibly because I don't encounter the same problems with air viscosity, narcosis, mouthfill timing, contractions etc that make equalising such a challenge on deep inhale dives.

I don't have a problem with pressure adaptation on deep dives. I think I'm a bit lucky in that regard.

Edit: Looks like Chris got in first. He pretty much summed it up.