That is one good price; we have a lot of them from different providors and the cheapest is around $800. Are you sure that is a full T1 and not a partial?
In our shop we do thousands of trades a day; every day we probably have ten to twenty entry errors that someone picks us off on; it is part of the business.
We make a business of picking off MMs; and sometimes they pick us off ...
I disagree; capitalizing on mistakes is what we do.
If I sell a market that is tanking, and someone else buys it from me, and it continues to go down; he made a mistake that I capitalized on.