100 hours asks a perectly reasonable question, and gets responses saying he should know better as he could be a CPL or an instructor.
Maybe 100 hours is very happy as a PPL and is just showing a professional attitude by trying to improve his skills.
None of us is perfect and we should all be learning something new every flight, so why not answer in a constructive manner instead.
My answer to his question is, I may not know to the inch, but generally in light aircraft I get an overall perspective from peripheral vision. To be honest I am unsure exactly where I do look when landing, but I am not looking directly downwards through te side window, although as i said peripheral vision gives me my clues.
However in an open cockpit taildragger I tend to have my head out the side to try to get a beter view!