Sometimes having a rest is actually very beinfical to technique. It gives our fingers, hands, arms, etc. time to recover and recouperate. It is important to build up strength and speed and stamina through every day trainning, but we can only improve so far without rest. Like an athelete, taking time off means we will be able to pass of previous peak. Yes, it may mean a few days of playing a little slower than we used to, but in the long run it means we'll only get better!
I've forgotten the name of this method, but it works, for atheletes and, more importantly, guitarist!
I realise now, having type this, it wasn't actually what your question was about, but hopefully someone'll find it useful! Comments anyone?...