You miss my point: while I am entering a password for future use, like during set up or password change, it is nice to see exactly the case sensitive password characters being entered. Many secure apps provide a check box or button to "turn on" display of letters when setting up a password. If I am alone, certainly there is not a security reason to prevent me from seeing what I am typing, if I so choose.
If I am not alone, I do not check the box and I type blind.
If I am alone, as is typical with administrators when administrating, then I click the box and voila I can see the letters I am typing. Since I am entering a password for future use, it certainly does not need to be kept secret from me for security reasons. I am not asking for this during login, but rather only when "setting up" a password. I have seen this feature in other secure wifi setups and noticed it "missing" from D-Link.