Just seems kind of funny ... you have people who have experienced the IMA version of "aiki" saying basically the same thing ... it's different and you have to train differently to get the skills. And then, you have all the people who haven't experienced the IMA version of "aiki" saying just train more in what you're doing or do some heavy work.
So, I guess the decision is yours for which you think is going to clarify the issue ...
There is an issue?
Look at this atricle by Tim Fong and Rob John (a good article BTW) on Aunkai and the first image of Akuzawa doing tenchijin. http://www.aikidojournal.com/article?articleID=699
He is in the posture of bearing under load. The second diagram below it shows two arches. What do arches do? Bear loads. Their use of tension to form continuous connection through the body is simulating the virtual bearing of such a load. ACTUAL bearing of load makes those connections without any complex or virtual simulation involved.
"Weight transfer" is a real body problem in a loaded condition -- not a construct of one. Tenchijin is even DESCRIBED as simulated weight bearing in Ark's interview http://www.aikidojournal.com/article?articleID=701
If you squat to lift a fifty or 90 pound back of cement and then lift and toss it to one side -- you just did shiko - under load. Trust me, if you toss a couple or twenty of those puppies you'll feel the "piano wire" tension all through your body, no worries.
Look at this series of descriptions of the exercises: http://unleashingfong.com/martialmov...Aunkai_Methods
Have you ever worked a post-hole digger in really hard soil in a deep hole requiring put your weight drop in to accelerate the spoons? -- You've approximated mabu.
Working the top of a ladder and needing to reach that spot JUST out of reach? So you raise the leg to prop it a toe against a wall while keeping your weight centered firmly on the ladder to get that LITTLE bit of extra distance to reach for the work in front or overhead ? Wobbling ladder bad, balance on ladder good. Congratulations -- that approximates Ashiage.
Just whacked the bejesus out of your thumb with the drywall hammer ? Wanna drive your (uninjured) fist with everything you got behind through that damn sheet of drywall (both to show it what-for AND regain the all important Symmetry of Pain
)? Or try driving your fist through a sheet of drywall with your fist in contact, if you can make it go "pop" -- congratulations. You just approximated GO.
Lift a bucket of mortar to someone on the ladder pointing brick or laying block. Gee. -- Agete.
Pick up a sheet of plywood on one side, brace it over your head pivot forward to flip it over and drop it on the other side. tada -- Shintaijiku. (for this type of motion it could as easily be bags of rice, bales of cloth or better yet --- kegs of BEER.
It is not an argument -- you can simply see it. Moreover, anyone can do it -- there ain't no secret. If you do it enough, and do it to miminize effort so you are not so tired at the end of a day you are starting to learn efficient movement under load. And you get demonstrably better wiht great incentive. And do something useful into the bargain. That is the foundation.
IMA is trying to supply the lack of plain old lack of whole-body hard work that ALL martial traditions grew out of. Maybe even successfully, but that's the source of the lack they are addressing. Most people doing martial arts these days are urbanites, and the likelihood of having a a significant experience of heavy physical labor is very, very low unless they like it or have no otehr choice,m and let's face it martial arts are for most people a lifestyle choice and most people doing that kind of work these days don't think in terms like "lifestyle." Having a foot in both worlds is an increasing aberration.