My deadlifts have been going exceptionally well this training cycle. Last week I worked up to 700 for a single which is what I'm planning on opening my deadlift with in 6 weeks. I wanted to work in some rack pulls to work on my lockout and went up to 800 pounds and done it no problem but ever since then I have had a strain feel in my back right under my lat. This week I deloaded and only went up to 405 and my back still feels like crap. So I'm looking for advice with 6 weeks out should I take a week, maybe 2 off from deadlift and then come back 4 weeks out and go maybe 80% or so to see how it feels? I plan on putting some heat to it after work this evening. I have really high hopes of an 800+pull the way my training has been going and this setback is driving me nuts. Coincidentally I have a video of the DL session I am referring to. Towards the end of the video you can see my expression after the rack pull that I knew something wasn't right.

http://www.youtube.com/watch?v=zqiI0-myc4E&feature=plcp