Cmcmurdo - I had two problems, if I laced the boots tight enough to prevent bashed toes (i.e. keeping my foot tight to the back of the boot) then I would develop a terrible aching pain in the soles and at the back of the heel as a consequence of the tight lacing preventing the structures in my feet moving and doing their jobs, in effect I was holding the whole foot far too rigid.
So what I needed to achieve was looser lacing across the top of the foot, but very tight lacing around the ankle, to hold the foot in place.
In truth, the usual position for lace locks on boots (i.e. at the 'crook' were the lacing turns vertical up your ankle) tend to achieve this a bit, but I added to it by simple winding the lace around itself a couple of times between lace hooks. The friction created means that if you pull the lace tight above the extra winding, it won't pull through and tighten the lace below the winding, means you can achieve different 'zones' of tightness.
Edit: Matt's link explains it perfectly. Basically take some time to experiment (or buy the right sized boots!
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