Most touring bindings at some will get clogged up with compacted snow/ice, especially the framed versions. I recommend having a small lightweight combination pick/brush in your backpack so when removing/installing skins you can give the bindings a quick poke/brush and then you'll have no problems whatsoever. The best brush I've found is a stainless steel brush that's made by Stanley & comes in a pack along with a nylon and brass version for about £3 from B&Q: http://www.diy.com/departments/stanley-abrasive-brush-set/30496_BQ.prd
Simply cut a bit off the end of the plastic handle of the stainless steel brush and whittle it to a blunt point so you now have a stabber/pick to break-up any compacted snow/ice and a stiff brush to clear out the snow. The blunt point is also great for cleaning out the toe & heel tech inserts in your boots as it won't scratch the inserts which would actually trap moisture & encourage icing.