The lye is what makes it work. Its not a compound that by itself works fast or slow. What companies have developed over the years are ways to buffer the lye to keep its effectiveness, but not allow it work at full strength (think drano fast), but slower for better application. I think that is as best of an explanation I can give.
I can understand the underprocessing issue, I suppose there is always that concern of over stretching the hair strand that more than not occurs with combing as a means of smoothing, thus creating strand weakness - breakage. Unfortunately, that breakage doesn't occur immediately after the retouch, but it is a continual weakening of the strand over time.
I have not found a better method either, but there are very firm applicator spatulas that are chemical safe. I would try those.
