Thanks for the responses. You have all provided a very good sounding board. If you saw the ups and downs I do on rolling dirt believe me 30 secs per mile slower on the long runs is in line. The other factor for long run paces is simply recovery. You don't recover as fast at altitude as you do at sea-level.
I think Sue hit the nail on the head the best. My marathon pace “zone” is uncomfortable. I keep thinking that marathon pace should feel easy (maybe it does for some) but to me it feels fast. Training for the shorter races I am either doing fast stuff at sub 6 or long stuff on rolling hills at 9 min pace. Nothing in between.
I will continue to incorporate more miles at “marathon” pace and hopefully that pace will become more familiar. I did do a 30k at altitude a couple years ago at 6:23 pace and for some reason that did not feel so bad. I need to try and recapture that feeling some.
Ryan's comments on the threshold work. I think your right there as well. I will prob. just break up my threshold work into more manageable chunks. I was going to do that tomorrow already since I have the 10 mile race on Monday. It will be more like 3x2k with about 60 seconds easy between them.
As far as not hitting pacing due to leg fatigue, that is prob. true to a point. Having some leg fatigue to me at this point (14 weeks to go) is not a bad thing. Just an indicator that I am in the midst of heavier training. I have been here before and am able to keep my confidence that the legs will be there after some rest/taper. Fortunately I have the 10 miler this coming Monday and then a half marathon 7 weeks after that to provide some fitness feedback.
Again, thanks for taking the time to write.