I use waxed laces or oiled leather laces in my wildland fire boots and they keep everything from slipping which is nice so you don't have laces coming loose while you work. I haven't used them in my hiking boots but I'm considering trying them to keep my boots tight throughout the day.
MattB - sorry to hear about the shoulder. In general, I'm not trying to be able to necessarily get the laces much tighter, I am trying to keep them tight once tied. I think I will give a set a try and will report results after I use them a bit. Thanks for the opinions all.