There ought to be a private way to communicate a thread-starter’s typos and other nits” to him/her, such as a Typo button-plus-brief-message box, similar to the Report button. When authors fix these nits they do a service to site-visitors, and when visitors bring nits to the owner's attention they do him/her a favor, in the same way that it's a favor to tell someone his/her zipper is undone.
But it annoys lots of readers when they encounter these helpful hints in the public space, so the nit-picker is sometimes accused of being a grammar-N*z* or engaging in captious criticism. It’s an unsatisfactory situation all around, which could be resolved (mostly) with a simple Typo button.
Of course, activation of this feature should be at the thread-starter’s option--even down to activating/de-activating it for individual threads. He sometimes (or always) might not want to inhibit his heat-of-the-moment blogging by worrying about typos.