That's an interesting thought. I always felt just the opposite.
I sort of operate on the premise that Less Is More. If you keep giving people extraneous information, they start tuning it out.
For my team, if you get an e-mail that says "MATCH REMINDER: Monday, Nov. 1 at 9:30 pm at Sommerset Country Club v. Walker team", you had better wake the heck up. Because it means one thing and one thing only: You are playing a match that night.
When I am on teams where I get line-ups/match reminders and I am not playing, my heart starts pounding as I scroll around hoping like heck I haven't screwed up and forgotten about a match. Then I find that, no, I wasn't set to play. False alarm. After a while, I am just a little slower about opening those e-mails, because they are mostly false alarms.
Regarding the risk that someone won't get an e-mail if you only send it to the people who are playing . . . I absolutely insist on an e-mail reply. If I don't get one, I re-send. If I still don't get one, I get on the phone. Problem solved.
Well it may be different because in your league you have many matches at all sorts of random times and dates during the week.
Our's are always on the same night, so Im only talking about everyone receiving one email a week about the match, and we typically only have between 4-6 players who are NOT playing that are going to open it, see they are not playing and then probably close it. (unless they want to show up and watch which actually does happen around here)
If our matches were all sorts of random days, my way wouldnt work for me either because not everyone checks their email 24/7 at any random time.
Otherwise if lot of other issues come up I am aware that sending out too many emails is confusing, so I usually have to start calling people because I agree with you, when they get too many they begin to ignore them (which causes a lot of problems)
I also try to make sure they are not too long and just stick to the important parts (like "PLEASE SHOW UP AND DONT BE LATE!!!!").
Also a lot of our players are people who work all day, they dont have time to be screwing around looking at spreadsheets or checking websites daily. It was hard enough to get them to use email so Im glad they at least check that.
I still make plenty of spreadsheets (to show them how often they are playing, keep track of our team schedule, keep track of money, availability, etc....). But if I had to rely on something as important as having them actually show up, I wouldnt leave it to a website to expect they know about it. (websites are just "there", you have to ASSume people check them, emails are sort of like notifying them that they are to appear)
Sure false alarms suck as well. But when you combine randomly timed emails with selective emails, you're just asking to have someone not show up because they "missed" a email.
Ive been on both types of teams, and I would feel a lot better receiving an email to the whole team if Im not playing, then no email at all. Sure Id rather play but it's not like NOT hearing from anyone makes me feel any better about it. (great, not only am I not playing, they didnt even think enough to let me know what's going on....)
Perhaps you dont care about your own teams or how well they do, but lots of players do, you'd be pretty surprised. That's part of the fun of being on a team, versus just a random assortment of players who just show up for their personal tennis match.