Regardless of which you play, there are likely to be frustrating, unfair, perhaps unsolvable puzzles present. Modern players often have the Infocom invisiclues at hand while they do so.
There are some pretty nutty things buried in the game, though - there's a spot in Zork 1 where by typing "temple" or "treasure" at the appropriate location you can teleport from one to the other - the supposed hint for this is they both have a granite wall. WTF?
I believe at the time, as a teenager, I finished most of the Infocom games available without using clues - it can be done. I think I never got the optimum outcome for Deadline.
I recently (this year) finished Starcross without hints or clues, aside from the copy-protection "map" at the start.
IIRC, both Witness and Bureaucracy had physical stuff in the box that didn't look like copy protection, but without which it wasn't possible to finish the game - e.g. There was no way to figure out some things in Bureaucracy unless you read the included copy of "Popular Paranoia".
This might not have been such a problem if I had played the Zorks in order, but I bought Zork 3 before Zork 1 because that was what they had in the shop. Otherwise I might have seen the verse in Zork 1:
"Oh ye who go about saying unto each, "Hello sailor", Dost thou know the magnitude of thy sin before the gods?"