I rebutted that point with a detailed examination of what the player learns from each Fun level. That's not just hypothetical; it's how I learned the game. And sure, it didn't put me in a position to cope with really difficult puzzles (even solving "The Steel Mines of Kessel" on Mac took me ten years after beating the rest of the game); but it did equip me with the knowledge I needed for the mid-Tricky levels where it stops holding your hand.
What you are saying here actually doesn't stand in opposition to what I said.
As you just outlined, the Fun levels can help to prepare the player specifically for the
Tricky rank - as it should be. There are still things that they don't teach, like the three-builder-wall, digger pits etc., but if that's kind of the point of the solution of the Tricky to Mayhem levels in the first place, i.e. having to find this out, then it makes sense for the Fun levels not to spoil those things.
In the context of original Lemmings as a standalone pack, this works.However, we're talking about preparing players for the difficulty of custom packs here . And most custom packs fail spectacularly at what Fun accomplishes in this regard.
No wonder, because, as we agreed upon before, custom packs tend to exceed the difficulty of Mayhem even in the early ranks. Hence, I'm not saying this is an easy thing to do!
But it does seem necessary in order to avoid a further division of the already small player base.
In the "Immediate turnoffs" thread, I pointed out how in my view, most 10-of-everything levels in custom packs are more akin to the Tame rank from ONML than to the Fun rank from original Lemmings. The Tame rank is infamous for its insignificance before the first somewhat challenging level hits the player out of nowhere in "Dolly Dimple" at the beginning of the Crazy rank.
That is precisely what you do NOT want, because that is what will make new players quit your pack. They will likely even feel somewhat "betrayed", because they were lured into the pack by these ridiculously easy levels, only to have the pack reveal its true face at the beginning of the second rank. And especially since the beginning levels were so easy, the players will most likely blame themselves and their own stupidity - how can it be that they suddenly have no clue how to approach a level, after the preceding ones were absolute cakewalks?
Packs that do this lie about their actual average difficulty by disguising themselves in a sheep's clothing of easy any-way-you-want levels.
I gave myself the nickname "he who usually only makes it up to rank 2" to joke about my own inability to solve harder packs, i.e. blaming it on my own stupidity indeed. But now we see the effects of something more systematic, in form of a widening gap between skilled players and casual players.
What was already kind of a weakness of original Lemmings - i.e. players who find out about three-builder walls, digger pits etc. get past Tricky, the rest don't - is multiplied in custom packs: There are people here who can solve almost anything, and people who can solve almost nothing - because nothing easier is there, at least in New Formats.
but I would respond that they have to get from A to B first
That is usually neither the ambition nor the task of a custom pack. Any new player can be expected to start with original Lemmings to get familiar with the skills, or, specifically, with a NeoLemmix introduction pack that actually shows you what all the new skills do, as well.
If you want those introduction levels to be part of your own pack, as well, great for you - I also like teaching players those things.
However, in order for that to work, you must, must, must adopt IchoTolot's ambition to have your pack be able to "stand on its own", as a standalone game. You cannot rely on other, easier custom packs to teach the player stuff in the meantime so that they will be able to beat your harder levels afterwards.
If you use your "Fun" rank to get the player from A to B, i.e. teach them about all the skills and game mechanics, then your "Tricky" rank must take them from B to C.
As however many custom packs feature this sudden spike in difficulty once the creator starts dishing out their "regular puzzles" after the any-way-you-want levels, you have A to B on rank one, whereas rank two takes you from, say, E to F. Yes, there are people who can learn something from the levels on your second rank - but it's not the type of people you have just "created" with your rank one; it's a different type of player. The ones that have played other packs before and now take a shot at yours. Those people were probably bored to death by your rank one, because they don't need to get from A to B, they're long past B.
I actually enjoyed how nin10doadict did this in CasuaLemmings - he's also the one who made me use pre-level texts much more often than I would have done otherwise. You can tell he specifically set out for each level to teach the player one thing, and one thing only.
The main issue with open-ended 10-of-everything levels is that you
can try almost anything, but you don't really
have to do anything specific. And while it might be fine to have such a "playground" level either at the very beginning or the very end of a rank, so that the player can test out their current amount of knowledge of the skills, every further one of those levels that gets added in succession weakens the purpose.
In short:
Skill-restricted levels are the lessons. That's where you teach the player.
The 10-of-everything level is the schoolyard. That's where you send the player to take a break and toy around.