Yes. And, given awareness of those handicaps, it is a wonder that biologists can appear so confident about their ability to distinguish between the hypothetical and the intuitive in their observations regarding the action of selection upon this or that trait. The only recourse seems to be to resort to extrapolating backwards from observed forms, on the basis of the assumption if it exists, it must have been selected for (not to mention the assumption that if we observe it, it exists). This really does seem to involve an 'appeal to imagination' not entirely in keeping with the highest standards of scientific rigor.
The conclusion (though somewhat tentative) seems forced: this is a weakness in evolutionary theory -- or at least in the way evolutionary theorizing, as a human activity, is conducted.
Well, I donÃ¢â‚¬â„¢t think that method can be entirely dismissed (you work within the known), however like any Ã¢â‚¬ËœtheoryÃ¢â‚¬â„¢ itÃ¢â‚¬â„¢s tentative dependant on new information. One thing, the comments made WRT Ã¢â‚¬Ëœextrapolating backwardsÃ¢â‚¬â„¢ are these remarks taken at face value or are they serious scientific theories?
There is only some much that can be deduced from the past. It is a limitation but we should not stop to attempt to make predictions upon what can be found out. ItÃ¢â‚¬â„¢s the sort of equivalent of retro-engineering.