It would seem like ALL creatures should be literally COVERED with all kinds of INEFFECTUAL 'features' then!!
The more complex the organism, the more often you find features that have little to no survivability benefit - right down to the DNA.
I bet if you took a few moments of thought, you could come up with a couple examples in your own body. Not everything in an organism is there for a specific purpose, sometimes things are just left over from earlier development.
Now, if we go to your ludicrous extreme of "literally covered with all kinds of INEFFECTUAL 'features,'" guess what happens. The sheer mass would then become limiting for survival and thus a pressure for elimination. But if there is no pressure for elimination, features tend to hang around for a long, long time.
Genomes examined do exactly that. Not all features need be expressed, but there may be (partial) code for them. The human genomen has lots of virus DNA in it.
Evolutionary prediction made; evolutionary prediction fulfilled.
Shaving, waxing and electrolysis will help.
What is the function of the capacity of the cow to invert her uterus frequently upon calving? What is the function of the propensity to play tag, in crows? What is the function of the vistigial webbing between my forefinger and thumb? Nature throws craps, and the results are unevenly distributed over the the efficiency spectrum--to no biological scientist's great surprise. All features cost something to maintain. For obsolete features, if the cost is great, the elimination is fast, if the cost is insignificant, the elimination is leasurely.