Hi
I think both kidstyx and Nireshan are on to something in mentioning the timing/deferral difference of Additions to Benefits compared to the other types of with-profits. I think this is a tricky point to explain(!!), but I'll give it a go....
(Note that Section 2 tries to describe it too. Also for exam purposes, the main Core Reading idea that, in countries where pricing bases are prudent, the same prudent bases might be ok for reserving, is probably sufficient.)
For revalorisation & contribution, we're broadly ok to use the prudent pricing assumptions as reserving assumptions. We need our reserves to be prudent and reflect future bonuses in line with PRE, and this will be achieved. Any better experience than the prudent pricing / reserving basis can be simply be declared as bonus in the year that occurs.
For Additions to Benefits, we can't be so sure that use of prudent pricing assumptions is ok: in particular that it will make sufficient allowance for future bonus in line with PRE. For example, if the current bonus rates are higher, then PRE would usually be to reduce them over time rather than in a single year.
Lynn