I think you should update the OP with the news that trial and error has been removed/toned to the point where you simply can't make mistakes.
Instinct mode replaces the map, you have to refill it by carrying out stealth kills (Conviction, anyone?), it's upgradable, it's used when donning a disguise, allows for you to 'read minds' on lower difficulties, highlights/shows guards, enemies routes, allows you to look through walls.
And let's not forget that the game supposedly enters a slo-mo mode when your cover is about to be blown, this allows you to do something to stay in the role of the disguise (pick up doughnut/something that relates to the disguise you've taken), which is admittedly cool, but was handled much better in BM with you having to find items relating to your disguise (tools, delivery box, etc) at the very beginning and not when you're about to be discovered.
SMH! :/