Desert Dude answered the question very well (as usual).
Re 3:1 ratio - It is not very common in distance running. I think the reason is that running, being an impact sport, is limited by in how much you can overload your body without getting injured. Typically you want to find your red line (danger zone) and train just under it. For example, a runner might get hurt if he runs 60 miles a week, so he trains 55 miles a week. To adopt a typical 3:1 build and recover cycle, in theory, he would run something like 70-80 miles in the 3rd week and then recover. The problem is, the recovery is now 6 weeks because he got injured.
Some marathoners wil do something similar, but it is to much more conservative proportions. A friend of mine would run 90, 105, 120 and repeat for several months. Notice he rotated every 3 weeks and his biggest and smallest weeks were really only 15% off the average week. Dena Kastor also did something similar, but on a two week cycle that looked something like 100, 115, 105, 120, 110, 125, etc..... So, to summarize, you will see runners do this to some degree, but it seems to really only happen with marathoners and to much smaller degrees than the typical triathlete cycle.
Liek DD said, I too prefer only two peaks a year. For a collegiate runner its typically one in XC in November and one in outdoor track in may. Triathletes have a hard time following a schedule like this because there is really only one tri season that lasts all summer. What one can do is either 1) simply focus on being in peak shape in September or 2) add another peak to an early race in May.
Your specific goal will determine exactly what to do after your 100 days, but in general you should add in some threshold (tempo/L4/Zone4/1hr race pace/90% max HR) training. You could proabably carry that through the whole summer. Pick two imporatnt races and sure they are at least 10 weeks apart. 6 weeks before each race add in some V02max intervals before that race. After the race take some time to recover. Build your mileage back up again, and then 6 weeks before the next race throw in the intervals again. If the races are only 10 weeks apart, you may want to cut your second set of V02max intervals down to just 3-4 weeks.
In the end, those V02max intervals will give you a great boost in performance at the end of your training, but they inhibit the rest of your training which provides greater long term benefits.
-----------------------------Baron Von Speedypants
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