That is fine, as long as the ac system accepts the input. If it does not, and you are simply manually adding corrections, (not in the system) that is a problem. That means the ac thinks it it here, while you think it is there. Again, it depends on the level of automation and system capabilities. In your statement, who is providing or correcting the MSA temp?
If your FCOM says no, I am not sure what the question is here. I would be curious what your SOP then uses as the temperature limit before you decide to correct? You with AC?
I missed answering this part.
We use tables (or these days the EFB for more accurate numbers) and add to step-down and FAF altitudes in the FMC. So that'd make it a manual entry. Where our SOP (and they changed recently) seem to differ from others is that FAF should be corrected when using VNAV minima, and you are within the temp limits for the procedure. I am aware of the FCOM SP.16, the EASA AMC, your POV as a procedure designer(?) but I just go by our OM-B. It tells us to correct FAF. Not really sure what the big problem is here. We correct up a bit, even if the path has been validated down to typically minus 20 C. So we come in slightly steeper, but not steeper than we would have on an ISA day. If temp is outside the limit for the procedure we fly it down to LNAV minima instead and keep correcting. Not with AC, but another northern carrier in Europe. We correct from 5 deg C (so ISA-10). That changed, we used to correct only from 0 deg C, after a 737 got a hard terrain warning approaching a level off altitude on a non-precision appr. It was a few degrees above zero and they hadn't corrected. They did come down pretty fast being a bit hot and high, but nothing out of the extreme ordinary.
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