Random numbers from CPU execution time jitter

The attack outlined is probably not applicable to a entropy generator input situation. The key problem is that the inputs are likely to contain the current seed of the random number generator in some form. E.g. if you have some new data x you want to feed into the pool, a straightforward solution is to update the random number generator state with "state = H(state || x)" where H is a hash function returning suitably wide result. Since we are going to assume that the attacker is not already in possession of the seed, the attack is not possible.