I haven't looked at this in ages. Are the current MS-DOS version solutions submitted for this thing even anywhere close to optimized? I suspect many probably aren't, despite efforts that have already been made a long time ago on the challenge threads here (but never yet translated into the form of a video or similar that conforms with the submission requirements used here).
Oh, definitely not even close, I wouldn't think. Although I'm sure Fun in of itself is probably not too far from an the actual optimized time.
Also, are we measuring based on game time or real time?
For the purposes of running multiple levels, real-time takes precedence, so that levels have to be done in quick secession. For the individual levels, the IGT timer is more important. This is sort of important for MS-DOS because things like pausing and pause glitches and such for are useful for stopping the IGT, whereas it would be particularly slow over a series of long levels to have to do a pause glitch every level (and going slower in real time) in order to make the IGT work better. I haven't tested all the consoles yet, so it's not yet clear what sort of things like this can or cannot be exploitable.
Either way, there are difference in the two ports in terms of how many physics update occur in a game second, and also how long in real time it takes between physics updates. As a result, the exact same solution involving the exact same pixel-level movement of the lemmings, will still take slightly different amount of time in each port, whether or not you are measuring in game time or real time. As a result that will make timings from the two ports not directly comparable, until you adjust for those differences accordingly.
Oh definitely. The leader-boards are separately by platform because the number of ports and their minute differences are so numerous and often tiny but still important. That's actually kind of why I was shocked the SNES time for Fun could be done that quickly, given that I assume the console version runs slower.
When emulating MS-DOS, increasing the processing speed allotted to the program doesn't really affect in-game play. The internal timer for the levels keeps the refresh rate locked. However, it does speed up loading screens so that the transition between levels is quicker. This however is limited, so there is a limit to how quickly loading screens can move, which is naturally important for keeping the playing field equal for MS-DOS users. I suspect this allows one to get through loading screens faster than a SNES would, and that sort of stuff can add up.
If more runs get added soon on different consoles, could be fun to take the current records and put them in the same video for comparison.