Pleasantly Confused

Today I planned on doing a MAF test followed by some 1 mile repeats,which I did. However, the results have me a little confused. The MAF went terrible, from a pace vs HR standpoint. A total backslide from my last test. I don't know if this means I'm ready to add more intensity. Or did my drop off in volume last week have that dramatic of an effect. Or was it just a bad day, dehydrated etc. I don't know. But since I'm 8 weeks out from Portland I will assume it is time to add more intensity. So I did that today in the form of 5 x 1 mile repeats. The plan was to do a ladder off sorts with times not distances. So I would adjust my pace for each mile. I was to start at 7 min/mi for 1 st mile then 6:45, 6:30, 6:45,7:00. This is how it turned out.
mile 1 6:50 HR 169
mile 2 6:38 HR 172
mile 3 6:21 HR 175
mile 4 6:41 HR 171
mile 5 6:49 HR 170

Now the part that is cool, to me. The last 2 miles felt easier and not just because I was going a little slower. The pace seemed slower and easier with each rep. My 9th and 10th mile of this whole workout felt good. I've always had a tough time with the concept of perceived exertion. Hard is hard and easy is easy and all the rest is either not hard or not easy....I know you'd think I was smarted than that. but I'm not. But today I actually could tell that miles 9,10 were easier from an effort standpoint than miles 6,7. I liked this workout and will repeat it a few more times before the race. I will track them and see if there is any trend.
AS for the MAF here are those numbers. As I said a little disappointing.

mile 1 8:40 HR 141
mile 2 8:49 HR 145
mile 3 8:46 HR 147
mile 4 9:00 HR 149
mile 5 9:29 HR 147
So HR's are a little all over the place and this was my 1st 5 mile test as opposed to the 3 mile tests I've done in the past.