It is recommended by manufacturers when using any quick dry paint that the surface to be painted is wetted prior to painting, helping flow and hence keeping a wet edge. Myself I use a hand held garden plant sprayer @ around £1.00 from any cheapo outlet to provide a mist wet surface that is not saturated. Easy!
As far as I'm aware, that advice only applies to Dulux Ecosure gloss, can't speak for the retail side of things tho. Sounds unnecessary and time consuming too. I've painted miles of "unwetted" trim without problems and got a great brush free finish. IMO, Bedec Aqua Advanced gloss and satin is just about the best out there at the min, both really easy to apply, after the usual proper prep.
Anyone tried putting the paint in the fridge for an hour before using? Seriously! Mr. HandyAndy - Really
The following is taken from the Dulux Trade 'Professional Product Guide'. When applying any water based gloss or satin, always use a synthetic bristle brush and dampen the surface you are painting before applying the product.