Is it permitted to say Tehilim for a sick person?

R.Harry Maryles on Emes Vemunah posted about Tefillah for a sick person http://haemtza.blogspot.com/ . I commented quoting Rambam in Hilchos Avoda Zara 11:12 who after forbidding to say pessukim from the Torah for physical relief quite vehemently, saying that not only is that considered magic it also includes the one who does it among Koferim in the Torah! because the words of the Torah are supposed to heal the Nefesh and not the Body. He then continues
"avol habori shekoro pesukin o mizmor mitilim kedei shetogen olov zechus kerioson veyinotzel mitzoros unezokim harei zeh mutar." A healthy person who reads verses or a poem of Tehilim so that he should be protected by the Zechus of reading, that is permitted. Note that there is no way that someone is allowed to read for another person. It is only permitted to say it for oneself.

Clearly Rambam does not allow for any magical incantations and he considers saying Tehilim for a sick person as possible Kefirah. (I say "possible" although Rambam is quite clear that it is, because I am wary of pointing at so many Jews who are nichshal in this unfortunately). It is very difficult to adhere to this prohibition as we have been so conditioned to accept it. In my mind though any mishap that a person experiences and it can be traced to a misdeed, and I mean traced to one rationally, then Tehilim would be appropriate. I as a businessman if a business deal goes bad, I usually can trace it to a decision that was based on greed or some other such reason. It is appropriate for me to read Mizmorim that deal with the greed and meditate on how to improve myself in the future. But a sickness that is not a result of the person's actions I do not see any reason that Tehillim is permitted.

I also pointed out that, even when healthy, one can only say pessukim for himself . The Meiri in Hibur Hateshuva explains why on the Yomim Noroim a Ba'al Tefila Hogun is required. He asks in general what is the idea of praying for someone else? The Rabbis tell us that when one prays for a friend the petitioner is answered first - why should praying for another have any value? He says that the idea is that we cannot tell a suffering person directly to take heed and review his actions. It would be very hutful, blaming the victim. However that person will not be helped unless he introspects and mends his ways so that he does not repeat the same mistake again.We do this indirectly by showing through our own prayer that we are looking at ourselves as that will encourage the sufferer to introspect too. On Rosh Hashana and Yom Kippur we look to the Ba'al Tefila to be a role model for the Tzibur on how to pray and do teshuva. ( No wonder Hibur Hateshuva is not a central sefer mussar in Yeshiva - In fact I never heard about it until I was pointed to it by an article I read by Moshe Halbertal). (to be exact the part explaining the Ba'al tefila is from Chibur Hateshuva- the part about the sick person I saw in a sefer of the same school - I could not find it now but it fits nicely with Meiri's thinking)

Now to say a Mi sheberach for a choleh and especially with name of patient and mother, to me that is totally nonsensical and probably ossur completely. Now I know that many other possekim think differently, but as everybody is machmir on every little sfek sfeka of a minhag by a little known possek , I indulge in being machmir in a vaday Avoda Zara according to Rambam.