Sentence:  One might disagree with the emendation, but that is beside the point: it would be inapposite to retain "oftost" and simply <WSD>underpoint</WSD> the first "t", since the change presumably introduced by the scribe is not a mere alteration of form but a misapprehension, and this should be signalled by emendation and the use of italics. 
Meaning of the word marked with <WSD> tags:  To add a dot beneath a letter as a proofreading or diacritical mark.