Evan,
Some of the simsii on that page look very similar to sempervivum, even the long leaved types remind me of 'Midas'.
I imagine there've been scientific studies done on the dormancy of pollen which I'm sure you could find with a bit of research. I'd also bet none of those studies were done on semp or aeonium pollen specifically
so you'd likely be left to make inferences of the data from other plants. Here on the forum and on a handful of other garden websites you'll find some of the leading experts on the various species of succulents, since it's such a specific bunch of plants without much agricultural or medicinal value my guess is the hobbyists are probably the most versed on the science behind the plants, we're lucky to have someone like Kevin who's been educated both formally and informally on the science behind sempervivum post regularly here. There are only a few other prominent hybridizers in the US and I doubt many of them have the background Kevin does, my guess would be that if he doesn't have the answers to those questions (regarding sempervivum) no one does. Perhaps there's a comparable fogure in the aeonium world who could give you some information on the subject.
As for my own experience, latent sempervivum blooms tend towards mutation and mutated blooms tend towards infertility. I usually don't get much viable seed off these cold weather blooms, perhaps it's because more pollen is dormant at the time of application, but with the bloom stalks often producing mutations such as rosette formations by and around flowers, oddly shaped blossoms and poor pollen formation, there are so many variables associated with the development of seed during colder months that I'd have had to keep a much closer eye on the process to have anything concrete to say here. Similarly I've not watched closely enough in the seedlings to say whether the colder blooms produced more frost hardy plants. I can't say the theory is wrong, but I can't prove it to be right either. I wonder what sort of studies were done to lead the author of that post to come to such a conclusion, was it tested under rigorous circumstances or is it simply a supposition. In any case, I can say that blooms can be induced through artificial conditions, and that a flowering plant which is exposed to cold weather after it's begun it's cycle will try to continue to flower, and that cold weather seed production is possible in sempervivum, I have done all of those things to some degree over the last four years, though I must preface that statement by saying any time you work against the natural bloom cycle of a plant you'll be fighting an uphill battle. Artificial induced and latent blooms are usually weaker, tend to have less flowers, pods and pollen exposed to adverse light and temperature conditions often seem distressed, as with most things the best results come when it's done the old fashioned way as nature intended.
That's about all the theorizing I can do during this beautiful weather on rare a day off work! Time to dive back into the garden for me, I'm busy finalizing my last round selections on the 2018 seedlings, most are getting room to propagate so if I do decide to name them I'll have nice little homogeneous colonies to work with, everything else from those early crosses is getting potted up in close quarters to be sold this spring.
-Sol
