Things being "on an edge." Other phrases that would be helpful to spice things up are "boundary, limit, threshold, extent of capability, point of failure, three potatoes away from total implosion" Makes me want to find the edge of something "granular" like some Utah sandstone and jump off it! lol Things being "locked down." (think establishing settings) However I picture malnourished individuals wasting away in a dingy wet cave because they have been "locked down." Maybe I just need to adjust my mental image and then lock it down. Any happy images for being locked down?