There are a lot of dimensions to this issue.  I sympathize with Allen because not every blogger is doing this for the hobby and the egotistical pat on the back that traffic and comments bring (myself included) — some are trying to make a go out of it.

Traffic DOES matter when you’re trying to sell ads to support yourself or business.

But let’s rephrase the question another way — do a lack of comments mean that there’s a gap in reaching the maximum traffic potential?

As part of a larger discussion about the utility — or futility — of socially driven traffic, I’m not so sure.  I love Allen (in a brotherly blogging kind of way), but when your bottom liine is governed by pageviews and uniques, I would argue that the level of user engagement is but a secondary metric. It is neither a necessary, nor sufficient, factor for success if your primary goal is traffic.

That is to say, I am of the opinion that in some (most?) industries, the percentage of active commenters are likely small with respect to the actual traffic coming in; and as a corollary, a lack thereof probably does NOT represent a giant gap with respect to maximizing traffic.

Furthermore,  I think its possible that traffic that is commenting is probably the exact opposite of the kind of traffic bottom-line bloggers want — they actively visit your site, and as a function of familiarity with your blog, they probably develop ad-blindness the fastest.

Factor in the first-adopter-ishness of Allen’s blog, and you can probably double, triple, or square, if you like, the likelihood of ad-blindness (and therefore, lack of clickage, and therefore, a lower CTR all things being equal) on all display ads.

Call me a [whatever you like], but for folks who are interested in the bottom line, the best kind of traffic is probably search-related traffic where people have absolutely NO allegiance are morely likely to read, and then move on — and possibly click on an ad in trying to find what they’re looking for.