Here is a better photo to illustrate why normal weighted text on my PW2 is too difficult to read for long periods of time. I combined two paragraphs into a one page book. The top paragraph is normal weighted Caecilia Condensed size 3 and the bottom paragraph is bold Caecilia Condensed size 3. I simply placed the text inside <B> tags.

For my eyes, the normal weighted text blends too well with the screen's dingy/dirty looking background and begins to appear less dark (lighter). I found that making the text bold helps significantly.

In this photo the normal text appears to be lighter grey and have less contrast, whereas the bold text appears to be darker grey with greatly improved contrast. In reality I suspect the grey darkness level is the same for both normal and bold, but the thicker/fatter bold text makes it seem darker. An illusion that works for me.