To the contrary, it may ensure bridges are there when you aren't, and may tell people how you feel when you're not around to.
Example: there are a lot of people whom I care about, but who - with no ill will involved - we've drifted off in our own directions as life tends to. We have vague contact info, and lacking that have mutual friends who can pass things on if need be. Come my demise, I may want a mass-emailing to thank them, ask for casual assistance for my dependents, and generally give a warm farewell. When I went in for heart surgery, I let one of the group know, in case it didn't turn out well; going in wasn't enough to warrant interrupting everyone and writing paper letters, but if I didn't come out someone needed to spread the word ("Hey, remember Carl? he's gone now, but says 'hi, thanks for the memories'"). Not worth printing up stacks of physical letters and burdening someone with putting then-required postage etc., but makes it easy to let people know how you feel when it's too much overhead all around now (hey, that's a big reason why people hate Facebook: too many updates), but when it is important to do so is exactly when you can't.
I'm thinking the parent comment was still right. Why not say those things now? Its not 'interrupting everyone', its keeping in contact. Its important to do that now, especially if you haven't in a while.
I was just thinking this is a lot like a coin flipping trick I heard once. You flip a coin for a decision, notice whatever you're secretly hoping the coin lands on, put the coin back in your pocket without looking at it, and do what you secretly wanted the coin to tell you to do.
With this service, go ahead and fill out what you want the emails to say... and then just send them.