The X Issue
Part of it involves the relative proportioning of the letter. For example, in the case posted below by R. Moshe the bottom yod of the Alef is totally out of proportion with that of the letter. As indicated, it is more like another "kav" rather than a "nekuda."
As with many other cases, however, it is likely that both of the above letters may be read as an Alef by a tinok. However, they may still deserve to be invalidated because we observe that it is truly a distortion of the letter's basic shape.
It is therefore, pretty evident that there is a certain amount of subjectivity that needs to be exercised by the sofer in cases like the above.
My question to the forum is: Would you use a tinok as an arbitrer in the above, or reserve their intervention strictly to a case resolving a doubt between two letters (i.e Dalet or Resh)? If it is not a she'elat tinok, would you consider it a she'elat Hakham, or reserve the discretion of making the call yourself? Please feel free to comment.