Hi Blueflower,
Ours were graded for 'quality' on a scale of 1-4, with 4 being the best (I think). We only ever had between 4-7 fertilise out of the 5-10 collected, and of them, 2-3 dividing at the appropriate rate, so it sounds like a much lower success rate than you managed.
Of the 2-3 that divided ok, the quality the first time round was one 3 and two 2s. Second time, a little better at two 3s (although the more celled-ones often were the worse quality ones) and one 2. Last time, we got one grade 3 with 10 cells (at day 3) and finally one they described as 'perfect' at grade 4 with 8 cells.
In all cases, despite a zillion notices about how they didn't want multiple pregnancies, they always transferred two embryos at day 3 (presumably as the odds of it working were pretty low and they didn't think anything would make it to blasto) and there was never anything worth freezing out of the rest by day 5.
First time round the eggs were collected some unknown 'cytoplasm' (a random blob) was noted in the cell - this may not have helped.
I think the fragmentation is part of the quality score, where they look for evenness/shape of the divided cells. The first two times round ours never looked anything like the pictures of 8-cell embryos you see on the internet, it was kind of more a mass of bubbles.
It sounds good that the consultant wants to try other options to give you a better result. Although I think you had a fantastic collection/fertilisation rate. If you see them again, may be worth asking how they scored on quality? xx