There are a few challenge threads (mostly the ones started by namida) where we try to report no-glitch results alongside glitch results.
For maximum % saved though, you may be surprised at how few solutions require glitches (actually shouldn't really be that much of a surprise, given that in many ways this has always been one of the easier challenges IMO), especially with the original Lemmings levels. Cascade 100% is glitch free. Mary Poppins' Land 100% is glitch free. The lose-1 solution for Tricky 23 ("From the Boundary Line") is nearly glitch-free, minus one move [edit: actually I'd argue even that move might not count as a glitch, but regardless...] which even when discarded, still leaves you at lose 2. 100% solution for ONML Wicked 9 ("How on Earth?") is glitch-free. And so forth.
Here are a number of things to consider:
- In general, if you look across all different video games for challenge-style plays (eg. speedruns), you will find that most of them do accept use of glitches. At the very least, there will typically exist a variant where glitches are allowed.
- Glitch solutions can often be more spectacular, especially if the use of no-glitch leaves you with a more conventional solution that doesn't really do much better than the normal ways the level gets solved. This feeds into previous point as well--glitch solutions can be more interesting to watch so it's hard to discount them.
- Using a glitch doesn't mean an automatic easy shortcut, if anything, solutions using glitches are often harder to execute partly because glitches can be difficult to set up and exploit effectively. This goes in general for video games as well, and also adds to the "it can be spectacular to watch" point above as well.
- It can be harder than you think to decide on what is or isn't a glitch. In some cases it is pretty clear cut, but in other cases it is a lot more subtle. If you read through some of the glitch threads in the forum you will see what I mean. And oftentimes it is enough to merely employ behaviors or combination of normal behaviors in unusual ways, rather than outright glitch behaviors.
- As Proxima pointed out when he talked about playing the levels in Lix, oftentimes a solution will hinge on things that have nothing to do with glitches anyway. This is especially true with challenge solutions which often depends on timing or precision down to the frame/pixel level.
Anyway, I guess when time permits I can at least list out which levels' max-% solutions in DOS Lemmings and ONML requires glitches and what the no-glitch results would be.