As i explained earlier, Tosafos did not discontinue any Gezeira. He did explain why we don’t have to revert back to it when it is not Nahug. Tosafos followed the Mesora Conservative Jews change messora. Which one are you?
We view Mayim achronim leniently because of Tosafos. This is true of those of us who are Makpid on Mayim Achronim. We follow Tosafos’ Psakim anywhere that the concensus of Rishonim don’t disagree. If you found a place where we don’t actually Pasken Lemaase like Tosafos, that has absolutely no bearing on the point you are making.
You are doing to Rabboseinu Mitzarfas what the tziddukim did to the Tanna’im. Similar complaints; similar conclusions.
Tosafos’ “methodology” is actually straight from the Gemara. We don’t have the courage, usualy, to apply such answers that are used in the Gemara (Okimtos, Tarti Ninhu, Hava Matzi, Kechad Amora etc.) because we know our limits and figure it is our Lamdus that it limited, and that there is a simpler answer that skipped our brains.
This is the reason we find that it often takes a great Amora to give a simple answer when the Gemara was actually cornered into applying that answer in the first place. But since for all we know there might be a simple logic that will make everything fall into place we refrain from giving a cornered answer until someone with vast understanding and knowledge says that this is indeed the appropriate answer.
Someone I know once said that it is not necessarily a good thing to be Mechaven to Tosafos’ Terutz.
Applying terminology to Tosafos’ learning does not show depth of understanding Sof Daatam of Tosafos. It shows an intelligent narrow-mindedness which is very common in these shallow, sweeping, observations that are published in order to gain a suffix.