There are no stepping stones. The vast majority of mutations are very harmful so by mere random chance even if one point mutation could be gotten that was 'on the correct path' the chances of it surviving to get a 2nd good mutation are very slim indeed.
Also one has to understand that neutral mutations DO NOT SPREAD THROUGHOUT A POPULATION. A new neutral mutation only spreads at the same rate as the entire group. Therefore the percentage of the population is virtually nil (one originally and if the population is not increasing remains at one individual carrying the mutation).
There are also additional problems such as that similar genes perform similar functions. This restriction makes the great changes required by evolution such as the descent of man from a bacteria impossible. Evolution requires totally new genes and these are totally impossible by the laws of random chance as the full article clearly details. Now one can say that ONE (1) such gene might arise by chance just as a person buying one lottery ticket may win the lottery. However, one cannot say that such an unlikely event could have occurred the millions of time necessary to provide the new different genes required by the millions of species still present on earth.
Also one has to understand that neutral mutations DO NOT SPREAD THROUGHOUT A POPULATION.
False statement. If both your mother and father have a neutral mutation, you and your siblings will also have it.
A neutral mutation will spread at the same rate as the entire group. By definition, it has no influence upon the population in any way.
So far, we agree.
Therefore the percentage of the population is virtually nil.
Absolutely false, and a contradiction of your previous statement. If it is neutral, over time, it will spread into the population as a power of 2.