Let me say upfront that my palate prefers bourbons t'wixt 90 and 110 proof. Less than 90 the bourbon becomes thin and more than 110 it almost always becomes too alcoholic, hot, and tends to 'scald' my gullet.
Many other BE folks seem to also prefer proofs in that same range. In ruminating on this I wonder if the alcohol itself, even though tasteless, contributes by vitue of its ability to 'carry' flavors. I realize that in diluting whiskey out of the barrel flavors are likewise diluted, but I also wonder if more than just dilution is going on, i.e. if the alcohol could be acting as a flavor amplifier.
It is my own opinion, based solely on my limited experience, that aromas are wafted up more readily by the evaporating alcohol in higher proof whiskies. However, the same dilution argument can be made of course about the aromatic elements just being less concentrated and therefore weaker in lower proof bourbons.
To sum up, does the alcohol itself, in greater amount, enable (if I may use that word) more flavor and aroma to emerge from the bourbon as I am suggesting it does? I would also suggest that, for my palate, proofs above about 110 tend to destroy flavor rather than enhance it.