I don't disagree, but it's not just a matter of matches, is it? Piotr said in a recent interview, that the best thing for Caro to do would be to take three months off and practice. But "that would never be possible for a top 10 player because of WTA player commitments".
It's therefore strange to see Caro having last-minute additions to her schedule whenever she loses early. That's why I mentioned Charleston and Brussels. She could use those extra weeks for practice.
Now, Caro would obviously point out to us that she's still able to practice during a tournament week while getting some real match practice as well. True, but with every tournament comes an extra day of travel in each end of the tournament - plus press conferences during the week, player party, sponsor commitments and so on. It's not the same as a regular practice week.
And it's interesting to hear Piotr complaining that 3 months off is not possible, while Caro has piled up a massive 14 tournaments, when she could get away with just 7 (Vika) or 8 (Serena and Maria).
Caro's season wouldn't have been much worse in turns of race points if she had played just AO, mandatories and P5's (AO, Doha, IW, Miami, Madrid, Rome). It's easy to say in hindsight but this is one area that reains untested during Caro's entire career: How about playing less? Maybe it works wonders?
There is a general trend of mixed messages coming out of the camp though, so it's hard to know. Caro herself said she was in Charleston because it was nearby to The Masters where she was going to be next week. Charleston is kind of an oddball event, I mean it's in a terrible place in the calendar and leads to nothing, and unfortunately for the rest of the field Serena now tends to play it. Brussels I always thought was likely to be a waste of time, I mean things were unlikely to get dramatically better in a week, she stood to gain nothing from Brussels unless she won the title. On top of that it rained most of the week, so I doubt Caro got that much practice in either.
There is a key difference between practicing during an event and practicing away from events though. You are not really going to be working on much of anything during an event, it's more of a case of ticking over. Away from the court you can put in dedicated time to actually work on areas of your game for hours on end.
Piotr is probably right when he says it isn't possible to take 3 months off mid-season. I know people here like to say oh she can skip the grass season, but realistically due to outside factors (sponsors), that probably isn't really an option, unless she's willing to make a massive sacrifice (it would probably involve leaving Adidas etc.). One point that should be made to this though is Caro like everybody else had 2 months off in the off-season, this isn't a problem that has just started in 2013, they should have been doing this work in the off-season last year. I wonder looking back if the end of last season somehow gave her a false pretence that she was back when really she was still a long way away.
I know you say it wouldn't affect Caro's ranking much, on the face of it it's true. I mean Caro would still have 1292 points playing a "top 3 schedule" this year as opposed to the 1675 she has actually accrued (though this is slightly misleading because as said before she can only count 16 tournaments and won't be counting a lot of these points anyway). But there are other factors, firstly Caro said one of her main goals this year is to win a title. If she just played the events those players play, her chances of winning a title this year would be next to none. Secondly, Caro will have been well subsidised to play some of these extra events, especially Kuala Lumpur, Charleston and Brussels, I imagine she received a fair sum to play these events. This is probably nice when you are use to receiving big money just to play events. Thirdly, Caro has also always given a vibe of she likes to play lots of matches, maybe she prefers matches to practice weeks etc. (even if this isn't necessarily beneficial for her game right now).
To put one slant on your final question. The top players are able to get away scheduling like that, they will go deep nearly every event they play, it barely impacts their ranking at all. The others tend to have to play to keep their ranking up, which in turn equals a lot of money to them from sponsors. Azarenka use to play a boatload of events, but now doesn't because she doesn't need to. Her playing a lot of events would probably hinder her ultimate goal of winning grand slams. Most players can't afford to prioritise like that.