I love keyboard navigation. I try to use it whenever possible. In Tweetbot for Mac I almost always use the arrow keys to navigate. In Twitterific, when you clicked the right arrow key it would open the links in the Tweet. But in Tweetbot it opens the Tweet itself, which is nice too. The issue is that I open links more than I open Tweets. And the default Open Links shortcut is Cmd+Shift+L, a two handed shortcut.
So I solved this by creating an Application-specific keyboard shortcut in System Preferences that maps the left arrow to opening links. Voila! One handed Tweebot navigation.