Rinpoches laying their hands on the heads of their disciples & faithfuls is an expression of their compassion to them. It's a sign of approval. It's also a form of encouragement to them. It's also one of the many means used by Rinpoches to grant blessings to their disciples & faithfuls. It's a sacred act.
Never have I in my whole life heard of this being used as a means of assassination.
It's a very malicious of the individual to conceive this idea. Such an idea may be adopted by others in future should another Rinpoche become the target of assassination.
. Irregardless of whether this is true & the outcome of this attempt on the Dalai Lama, one thing for sure is, this individual has left a negative imprint on the minds of all sentient beings who heard this news, including myself, through the introduction of such a sadistic idea to our minds. Everyone who is reading this post should take act to purify his/her mind of this, so that this imprint will not ripen in the future.
Out of security concern, it's possible that the Dalai Lama will not be laying his hands on faithfuls for the time being, it will be sad for them.
When security becomes a concern, disciples & faithfuls wishing for the safety & longeivity of their Rinpoches, and those directly involved in their security, should regard their Rinpoches as ordinary human beings, so that they will be careful in all matters & not take things for granted. This is not an act of disrespect, because only by thinking in this way will a proper job be done.
I believe this rumour has also delayed the decision to lift the ban on Dorje Shugden.
If this tragedy really take place, pro-Dorje Shugden community will definitely become one of the prime suspects.
As for the Dalai Lama's statements in recent times regarding his longevity & succession, for onlookers like us, it's better to see this as an expression of his undying compassion for all sentient beings, this cultivates a virtuous thought in our minds rather than seeing it as a means to gain sympathy for political motives, which would be a view possibly held by the Dalai Lama's political opponents, we do not need to cultivate such non-virtuous thought in our mind like them, as we are not directly involved in the political struggle.