
A few years ago, I was in 770 davening Mincha, and i noticed that the Chazzan made a mark in his Siddur before he started Shmone Esrei. Curios as to what he wrote in the Siddur - which belonged to the Shul - i checked after he left as to what it was. I noticed that he made a mark in the Siddur near the point where on fast days you must say Aneinu.
That day was indeed a fast day, obviously he wrote in the siddur, to remind himself to say it, but it wasn't HE'S siddur, what happens if I used the Siddur the next day?? would i maybe by mistake say Aneinu on a non-fast day.
The truth is, that it's not the point what happens the next day, the question is right then and there, WHAT ON EARTH WAS HE THINKING???? It's not he's siddur, he must NOT write on it.
Today i was davening Shacharis, and a kind fellow that used the siddur before me (could of been yesterday, or a few days ago), took initiative to remind Klal Yisroel NOT TO FORGET Vsein Tal Umatar, how? He made a pen mark underlining those words!!!!
But it's just like the people who are Machmir, that if a hair falls out of their beard, they put it in a Sefer. But no, they would never ruin one of their Seforim at home. They just dump it in the nearest Sefer they find in 770.
I guess the Tfillin straighteners might be better.