I find this an interesting discussion and I have done some research of my operations manual and EU OPS.
The question, if I understood correctly, is: if we have to take into account N-1 landing minima, do we have to take into account at the planning stage N-1 landing distance requirements.
To me, not!
There are two regulations, sub part D and sub part F.
Sub part D talks about wx planning minima and stipulates that for a take off alternate you have to take into account N-1 limitations for the aircraft. So for example a B737(the one I fly) can't fly a N-1 cat 2/3, however, a EMB190 can fly a N-1 cat2/3. So for the first aircraft(B737) if the wx is below cat 1 I have to find an alternate that is above cat 1, for the second(emb 190) I don't.
Sub part F talks about performance requirements! Besides required enroute alternates, there is no requirement to take into account any N-1 conditions!!
So, to summarize, your take off alternate should have wx limits above N-1 limits for your airplane type(according part D) and comply with the general requirements(according part F) for being able to land within 60% of the runway with all engines!
My mind is scrambled with all the rules, but think about it! You can go to your destinations without having to take into account N-1 landing performance, your alternates don't have to comply with N-1 landing performance requirements! Why should your take off alternate have to?
It is only a WX requirement, related to N-1 limitations that have to be taken into account.
As a last argument, nowhere in my books, there is a dispatch chart for landing performance N-1(I sound like Yoda). Only FOLD charts!!