Seymour Hersh! Right.
You probably forgot this:
http://tribune.com.pk/story/889381/...-denies-claims-he-was-cias-walk-in-informant/
They had sufficient time to assess Pakistani military capabilities and discover loopholes to exploit when the time was right. Operations (e.g. Neptune Spear) do not occur one fine day. A lot of planning and preparation goes into them before they are given the nod.
Is it really difficult to figure out load-shedding schedule of a city? If you have informants on the ground, you can learn this fact rather easily. Heck, you can monitor blackouts from the sky.
That helicopter did not crash on the ground and explode. It hit something and
hard-landed within the compound. There is a difference between an actual
crash and what constitutes as
hard-landed. The commandos, on-board the
hard-landed helicopter, proceeded to complete their objectives soon after (one of them even wrote a book about this mission;
No Easy Day). While the raid was in progress, another helicopter (as a backup) arrived in the compound. When the objectives were met, they came outside and destroyed the
hard-landed helicopter with explosives [but its tail was on the other side of the wall and remained largely intact; we found it]. They boarded the other helicopter and left. This explosion attracted attention from the surroundings and Pakistani security personnel began to mobilize.
By the time Pakistani security personnel reached the compound, they witnessed two helicopters departing the compound. They initially thought that this was Pakistan Army.
FYI: Americans had modified the rotors of each helicopter (involved in this raid) so that they would produce different noise and fool any radar into thinking that they were something else during flight. The helicopters also flew in
Terrain-hugging manner in order to minimize the possibility of radar detection.