The new expert is very good at making things efficient. Therefore he is able to cram 500 troops on a boat that is sailing to adventure. This is no problem in theory if food is dispersed in correct rations, and people sit still. The problem only comes when it is to be effectuated: People steal food and move around, especially in bad weather, so there is a chance for loosing troop .. up to 250 actually (but can be 0 if you're lucky) ... There is even a 1% chance that the boat can sink due to bad wheather. If the boat sink, you'll loose both the general and the rationalist.... and good riddense .. that rationalist must have been an idiot!!!
The rationalist cannot cost more than 1000 gems.