I'm not too sure in honesty Grey, as last year was just as bad and yet enough decent 2yo performers came to the fore. Very often too, you're more likely to generate a high speed figure in heavy ground as the variance calculation from which they're all generated from becomes more volatile as the scope for error increases in line with the wider band of performance that heavy ground throws up. Some of the bigger figures I've come across have occurred on heavy ground, where one particularly well suited horse runs a fast time on a card where other horses might have taken it easy by comparison. Therefore, I'd have more reason to expect to see figures of 100+. Evening Time would be one such candidate who springs to mind. She ran a massive figure in heavy ground, but never went on to fulfill that promise, although she suffered a set back and one could easily suggest this was the reason.
If I were looking for a weather related explanation I suspect it's more likely to be found in the possibility that the better 2yo's have been running on ground that hasn't allowed them to advertise the merits of the true ability to the full as yet. I suspect this is quite possible, but the real prolem we have with concealed performances of this nature, is knowing which horse has put one in.
It's also possible I suppose that an unraced 3yo might emerge, but I wouldn't have thought that this was likely in time for May.
I suspect that those people who are knowledgable and blessed with an eye for being able to read a horse, probably hold sway over those of us whose lack of knowledge reduces us to the stopwatch for the class of 2008.