The biggest question regarding Tjeny (This or Thinis), is exactly what type of impact did it have on the political world of Early Dynastic Egypt? Manetho suggests that the city was the place of origin for the kings of the 1st and 2nd Dynasties and several publications that I have read seem to accept the idea of a Thinite Dynasty. It is agreed upon for the most part that the earlier kings of Egypt (ie. 0 Dynasty) probably originated from Nekhen (aka Hierakonpolis or Kom el-Ahmar). Considering the proposed location for Thinis, it would have been in the direct path of any conquerors moving north from Nekhen.

Toby A.H. Wilkinson lingers on Thinis as an important royal and political center in depth and offers his theory of its part in the unification of Egypt within his book Early Dynastic Egypt. His theory puts forth the idea that there were actually several royal families, one specifically located at Nekhen and another at Thinis. The royal family of Thinis emerged the victor between the two houses and it was they who continued the conquest and unification of Egypt.

That's one possibility. Another is vice versa, that the royal house of Nekhen chose to push North after subjigating lands South of their city. Providing they had a secure enough base at Nekhen, it would have only been wise to relocate their main force to Thinis, after capturing the city, to be able to continue pushing North. The city of Ineb-hedj (later known as Mennefer or Memphis) had yet to be built so Thinis may have made an excellent new seat of power.

And a third possibility is that of a political union between the royal house of Nekhen and the royal house of Thinis, providing there were two royal houses. Who's to say that a beneficial union was not arranged to unite those two chiefdoms enabling them to pool their resources and expand their circle of influence in a northerly direction?

Course, this is all speculation until we know exactly who unified Egypt and exactly how long it took to do so. Some prefer to think it was the work of one man, others that it took time and was through the efforts of several men. I personally choose the second option. In the grand scheme of things, Nekhen and Thinis are relatively close geographically. To the ancient Egyptians, however, that still would have seemed quite a distance.

I don't deem to know much about military matters, but it would seem smart to conquer an area and before progressing, make sure that area is secured. I would think that especially smart if the area in question would be able to cut off your route of retreat back to your own city. With this in mind, the royal family of Nekhen could have conquered Thinis, moved their operations there and for perhaps at least a couple of generations, based their further efforts from the city making it their new home. This would explain why it would be considered the city of origin for the kings of the 1st Dynasty at least. To state that a place is a city of origin, I would think that would designate some type of permanency, not simply a city that was conquered and merely used for military expeditions.

But as I mentioned previously, this is all merely speculation until more information comes to light through archaeological excavations. I look forward to the day when the location of Thinis is firmly fixed and such excavations can begin - it has the potential of unlocking a new chapter in the history of the Early Dynastic Period.