This is an interesting perspective on training.  http://www.samiinkinen.com/post/11347268687/hawaii-ironman-secrets

I think it mainly applies to people who are already quite fit but I do agree with some of the points.

1. No brick sessions. I never do them. I know I’m tired after biking so training isn’t going to change that. Some people claim “It helps you train your body to move after the bike” What do you think I do after biking? Lie in my bed for the rest of the day? I’ll walk, have other commitments and continue with the rest of my day so I think my body gets plenty of practice of moving after biking without a brick session.
2. Shorter distance exercises when training for long distance. When training for the Iron man swim I swam mostly 1.5KM  (30min) a day. I rarely if ever swam an hour and less often for more than an hour BUT I did swim allot (3/4 times a week) so my weekly swim distance was the equivalent of two long sessions. I swam the iron man swim in a good time and I didn’t feel tired.
3.  1 long bike ride and 1 long run a week. I think this is essential part of training. I’m not too bothered by what I do during the week (as long as I bike commute to work and get a couple of runs in) but I like to get these two sessions done.

The key message is don’t follow a plan for the sake of following a plan. Question everything you do and then alter it so it fits into the way you work/think.

PS – this week I didn’t manage to get a long run in but I did climb a hill instead. Even the best laid plans can be thrown out. Never be a slave to a plan!