OK, l would like here to clarify how l look at what is termed a wet fly, which for me is not related to any fly that sinks.
It is a particular type of fly of a traditional value historically, all be it there may be modern variations of similar nature.

The essence of a good wet fly is that it should readily sink when it lands on the water surface, granted there may be patterns that incorporate dubbed body that until they are wet will float for a short time, after which they will sink, unless you use a fast casting action that dries the fly out, if you do the odds are you are using a rod that does not have a mid flex action, we will deal with this issue at a later point in time.

Likewise if you have excess hackle and again the fly will not sink, not good. We are dealing with wet flies here.
If the fly does not sink as soon as it lands on the surface of the water you may encounter drag, and spook fish that would otherwise have taken that fly if it were sunk.
Which is the essence of a spider style/soft hackle.

Other factors l also consider are hook weights used for the particular flies l use at given times, as this matters very much at times, more about this later.

So to categorise how l look at wet flies it would be this, all be it there are variations.

Winged wet fly.
Winged/ with palmered hackle
Palmered hackle
Spiders
Soft hackles.

All wet flies will incorporate one or more of these elements over and above tails and body mediums.
But they also serve for different reasons and use given prevailing conditions at that time.

Ok, l would never use the word never so far as how a trout might react, however there is a basis of approach that is shall we say way more conducive to catch fish at a given time by the manner you are fishing.

For example. We are fishing a shallow water riffle run over good gravel substrate. The is a hatch of say BWO or PMD. The obvious choice here would be to fish lightly dressed spider patterns that represent the nymphs, and duns at stages of emergence or drowned duns, at different depths, all be it within the first 6 ins of the surface. We can have options here for 1 or up to say 4 flies, in preference at least two.

In this situation l would not choose to use say a Peter Ross, a Blae and Black or a Green Peter as examples, all be it one of those may work. By far the most consistent way to beat those fish is to use flies of a character that represent in some way the naturals the fish are eating.

Further more l would be fishing the spiders in a very different way than l would for the latter 3 flies named.
This is the only way you will further understand the art of fishing wet fly. Using flies that have to be fished in a imitative way.

Granted you may choose to fish downstream and fish all manner of soft hackles down and across and that may work, but you are not learning the skills of fishing wet flies in what l would term the right way so far as representation.

If there were for example a good number of fish feeding in this zone, the most effective manner of presentation will be up and at a across angle, and allow for the flies to drift at the same pace as the current flow.
If we opt for standing upstream of these fish, casting across and down the odds are we will spook them.

Therefore my approach is going to be a long overall leader at least 12 ft, maybe more, 5 and maybe 6x with 3 flies at least 25 to 30 ins apart presented in a dead drift mode.

Watch a fish take a natural fly, it will do it positively. You are aiming to present your fly is such a way as the fish does same.
I guess the best way to explain this is this.
If l told you to rig 3 dry flies and fish them without drag that is easy as you can see the flies and make corrections to the drift.
Now do the same with the sunken spiders, its not so easy as you cannot see them. Therefore you have to use other ways to determine that.

Which we will deal with in part two.

Davy