Truss rod: changing strings from 9s to 11s

[SKC Willie]

light strings vibrate more than heavy strings with the same output... so you need more space for a light string to vibrate than a heavy string.

this is what i was going to say. you can lower action with heavier string BUT you still have to press harder to get the notes to fret well. I personally like 11s on everything. My teles, my jaguars, everything. That's just what I'm used to and playing anything else feels awkward and uncomfortable.