I rarely “subscribe” to blogs. It seems wrong to me. If a blog welcomes comments, then I can comment. If it doesn’t welcome comments, so be it; it’s one-way communication. But to welcome comments, but only from “subscribers”?
Apparently that’s a kin to filtering the participant pool for quality — in reverse. Once you limit to subscribers only, you get “regulars” who think they own the place, friends who feel obliged to comment even though they have nothing to add to the conversation, and avatar-happy post whores looking for attention.
Tell me, what are the odds a sincere, intelligent and respectable individual will register at (insert blog name here) to post comments (friends and family excluded)? Pretty low. Not zero, granted, but much much lower than acceptable.
Requiring registration is reverse quality control. It eliminates pseudo-random input from high quality people passing by from outside your circle of influence (cross pollination). It raises the bar for minimum participation required to comment (I guess reading isn’t enough any more). Perhaps most importantly, it interrupts the user mission of commenting, inserting a value decision front and center (is it worth registering just to say my piece?). Usually, for me, the answer is no.
Does that simply mean that the “blocked” comment wasn’t worthy anyway? I’ll let the evidence demonstrate the answer to that question. Take a look at the “registration required” blogs and you tell me if the quality of the comments is as good as no-registration-required blogs in the same niche markets. I’ve looked, and made my own deductions.