I'm not sure how you'd show 'an omote and an ura version of every technique' without some tenkans? For me, those were part of the requirements of my tests starting from 5th kyu.
It seems the thing that has frustrated many of the beginners is the realization that for some reason ura isnt working in a particular situation where 'pressure' is applied.
Fact is every technique does not work for every scenario...sure we learn it, but for the most part there are specific instances where ura makes more sense then omote... [or vice versa]
Tsuki Csudan is a good example of where Kote Gaeshi Ura works better than omote...at speed. [not just me with my 2 years of experience, but my instructor with 10+ years experience agrees.]
Forget about tenkaning around, it is good only to the sissies. Cut him stright down like a thunder and unify him with a tatami as strong as you can. This is a Way of Aikido.
As far as this, I would tend to agree. If you have a stubborn strong uke, your not going to tenkan him regardless of your beautifully centered move. Once this happened at a seminar, and our 5th degree Sensei came up and showed me a move to nail him to the ground...
I think if you know what your Sensei expects, then you have more flexibility in testing...but it does take awhile to get used to it.
The key thing for your first test is to take it slow and do it correct. Even in higher kyu ranks, one of the senseis watching told the guys to slow down... [speed is good and necessary, and more than appreciated where we train] but for lower to mid kyu they want to make sure you have the steps and concepts of what is working and why.
If you think about speed, you wont execute the technique correctly... or rather, let it flow naturally.
Good luck on your test.