I'm not sure if you replied to it, but this is a sensitive matter in BB. So let me give you some info about it, so you are well informed.
* You can accept the offer, and let him know you will play TIE and have an agreement: Mutual TIE requests are looked upon as very unsportsmanslike by many BB-players. So letting people know you accepted will not make you popular. Yet it is not prohibited, even though BBs don't want to encourage it.
* You can ignore him, and pretend you haven't received anything. In that case you don't reply to him, and he doesn't know what to do, since he has given you some info about his intentions. Most likely he will play normal, since you didn't agree, but he can still opt to TIE, since he intendd it all along... Many will think this a good solution, since you don't react to an unsportsmanslike offer. It also brings you in a disadvantage, since you now will doubt about what he will play more then when you didn't get the info...
* You can react to him you don't accept the offer, and will play as you intended, without ofcourse telling him what it is, but it is a prety bad idea, since he will think you won't play TIe, and will probably play normal or even crunch to win the game.
He might have the same reaction when you don't react as well, so here, as well as in the second point, I think you are disadvantaged by his mail.
* You can answer him you will, and then play normal. This gives a big fuss, but in the end, he created a situation for you where you need to choose to benefit from it, or be disadvantaged. Since he sent the mail, there is no way you will have a neutral option. He forces you in a direction, and you need to do what is best for the NT.
The Dutch NT coach did this and immediatly he was blamed for unsportsmanslike behaviour, yet in the end, many agreed he did the right thing, since he was forced one way or the other, and choose the best for his team.
Personnally I would choose the latest. the result is that you will never get TIe agreements again either, since they will know they can't trust your answer. This is best for the team, when you are forced to choose, and it prevents a future in which users can blame or bug you about being unsportsmanslike.
Ofcourse the choice lays totally with you, and if you choose to benefit from the system of mutual TIEs, and like to be able to use it in the future too, it is your choice.
I just wanted to inform you about it, and what came out of discussions about this ealrier on... It is important when you make such important decisions that you are well informed about the concequences, because one way or the other, you will for a big part be creating your own future here...
I hope I helped you with this post, and whatever you choose, even if it's not the option I'd take, I won't blame you. ;)
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