That's a great idea. I don't have serious vision issues (just poor vision that is easily corrected with lenses) but I was recently making a series of Y-blocks for the first time and I didn't pay enough attention to how I was trimming, so some of my points were off. Once I realized what I needed to do, I should have added the tape to the opposing diagonal on the ruler. That would have made things much easier. Also I was cutting to 7.75 inches, and every time I lined a block up, I had to say "7.75....7.75....7.75" to make sure I was lined up correctly. A piece of tape would have made that job so much faster (and quieter since I have to say it out loud
).