I grow all my phals in s/h (I've bought some species seedlings in bark and will switch them to s/h come spring) and do not use the "reservoir" technique, as I noticed that it keeps the rootball too wet. However I use s/h type containers, where the holes are drilled on the side and not on the bottom.
During the summer, I made the mistake of not watering them until the reservoir dried out but then I realised that all the new top roots emerging were drying out!
So now I water regurarly and let the water drain out completely. I have a better control of moisture retained in the clay pellets that way, plus the new top roots stay moist.