I guess no one has any reasons to use such a device.
My views on this are very simple. An egg is a living thing. Its either dead or alive. IF its alive, candling, weighting, measuring, messing with or detecting its heartrate, with not increase its chances of hatching. Any of the above only increases the chances of it dying. On the otherhand, a dead egg is dead and as far as I know, there is nothing you can do to make it become viable again.
Now if there was something about the way the heart beats that could detect errors in incubation, and further, there were known ways to fix those errors, that relate to those heartbeats, then it would be of benefit. As far as I know, that does not exsist.
Cutting eggs open, is very foolish and naive, as that only decreases the chance of survival as well. And please don't go taking that personal, as I know this from being foolish and naive. If an egg is obviously dead, you can do whatever you please with it. If its marginal, you really should not be playing around with it in the first place.
Of course aside from hatching eggs, I see lots of uses for this tool. It would be very interesting to me, to see if mucking with eggs, decreases or increases the heartrate. And if it does, as what stage of development would the embryo become aware of outside stimulis.
Again if someone could help me out here, I would would be thankful. F


