Sorry! English is not my native language and it’s hard for me to express my thoughts ((
In both cases pick adds some energy to a string - it’s a fact. Though in the case of already oscillating string it doesn’t matter much. String already has some amount of energy stored (that’s why it continues oscillating). When we touch the string with a pick that energy redistributes between two parts of the string. We are interested in the part between pick and bridge.
In that case the only way pick may influence string’s behavior is to absorb and dissipate that energy. Problem is: for most picks point of contact is quite small and materials are more or less hard, hence picks are not very effective in the terms of dampening string. It could be noticeable in the long run, but not for a short period.
There’s a period of time when pick is in contact with string while it still didn’t slip from pick. So, basically, there’s no much difference whether we hold it or pushing through. There was a thread of mine where I put waveforms of tremolo picking and analysed chirps. You could see that chirp time is quite short but it still noticable… Since oscillation frequency is high compared to pick’s speed you could assume it just pressed against the string.
Now come to think… may be that thread gave an idea to Troy for these researches?..