And hence the reason why I started this site.
That was making my head hurt. A simple question about training PRIOR to the specific IM build got the answer 'do a 14 week IM build'.
Anyway, wile not a coach and as someone who pays someone to tell me what to do, I do know what seems to be working and things that certainly did not. As the years add up I find however that some things change as the toal hours add up.
Pretty much the way I see it, in the lead up to your (that guy in the thread's) 10, 14, 16, 20, whatever week IM program you are training yourself to be able to do that properly. My forst IM I did off very very little training and when I did start a program with AP, I was effectively training to be fit enough for the next session. The actual sessions were not being absorbed the way they should have been.
So what is it we are doing here? Swim 3.8km, get out and ride 180km then run a Marathon. My personal belief is that not including your first Ironman, at any time during the year if you are in for a long term haul towards your best IM in following years, you should be able to complete and Ironman distance. When I say complete, I mean just that. Nothing to do with times or anything but just the basics of all the distances back to back. If not this, at the very least at the end of your base period right before your IM build you should be able to complete the distances all together. This is what I would want for ME though.
Now that said, lets look at the reality of it all. Heaps of this is to do with where you are in your triathlon 'life'. I know I had very little confidence in my fitness a few years ago and as a result I was certainly of the more is better crowd. I think that really, if you can avoid injury, motivation loss and sickness, this is the way to get better faster. The 10000 hours thing gets thrown around heaps. This is entirely true and I have a personal eample of exacty this that is 'Trent Champmanesque' in proportion.
As some may know, I used to compete in Archery. As a youngster, I won a Junior World championship, held all the National Senior records for the Indoor events in my first year as a Senior, was the first person ever to shoot a perfect round.... then found beer, girls and cars and put it on hold. I made a comeback in my mid 20s and off very little practice came 2nd at the State Titles then straight back into retirement. In 2005, the World Championships were to be held in Australia so I got myself involved again and hit it very hard for a year. I very quickly got back to the level I was at and then some and long story short, I blew myself away and got myself 5th place..... after 8 years out, on the back of 12 months training. How is this relevant to this topic? In many many ways.
The other thread drifted into the PIS thing and many points were lost. One that is very obvious to me these days and used to shit me to tears is that training discussions on the internet always end up being about people glossing over the big picture. When I first joined transitions, I would always read about guys qualifying for Kona on 12 weeks traning!!! What was never added was the 20 years they have had in the sport and all of the lessons they have learned. Goony is a great example. I thought he was a recent blow in for the Ironman thing but he was doing 10 hours at Forster 8 years ago and finally qualified last year. In my Archery example, I had thousands of hours behind me. I knew all about form, technique, equipment, competition pressures, rules, you name it. This is an enormous head start that the newer player to any game would not have. This goes to show that the answer to the original question that you pose Steno is 'It depends'.
It depends on what the standard required is in the mind of the athlete and the standard that is 'expected' by the universe based on potential. I know it is not a decent answer to a very simple question but really, there is so much to such a thing.... however, there is a very generic answer that I can think of for a balpark type outcome.
Now for the Ballpark answer. 90 minute swim, 4 hour bike, 2 hour run. All off season, alternatng weekends bike and run. Half you Ironman total hours per week. So, if you are a 20 hour IM prep guy, 10 hours a week in the off season. I think it is also important to have some intensity in there. As you aproach your build, start adding sessions in the week so that your hours start increasing towards those that you will be doing in your program.
A very simple exmaple week is what I am doing these days while I get back into some traning. (sanitised)
3 swims - 2km
3 Bike - 2x2 hours 1x1.5 hours Half IM effort
3 runs - 2x40 min at half IM pace, 1x 60 mins easy.
As I miss sessions here and there, it ends up being 7 or so hours a week but is more like a 10 hour plan. This is to get me ready to start the base phase. What that will entail I don't know as I have not got my plan yet from 'coach'.