Which would then change other lines that are output before the format is reset. So that would result in having to repeatedly change and reset the format.
Again, I provided the code that echos the line and resets the format-- so yes, you have to repeatedly change the format, I already showed this in my example, but this is irrelevant for two reasons:
1) Presumably, each "actual time" is different from the last, so you HAVE to change the timestamp format for each line no matter what.
2) You don't need to reset to the original $timestampfmt until the end of the set of lines (if you echo more than one at a time), though. My example echo's a single line, but you would loop /timestamp -f and /echo -at continuously. mIRC is single-threaded-- you can guarantee that no other code will execute while your buffer loading operation is being performed.
There shouldn't be any performance issues with doing this, by the way-- /timestamp -f does a very simple memory manipulation. Resetting the timestamp format won't do any harm.
Never said it did. A separate /echo flag to not log the timestamp would work.
Then you are asking for a new feature
, not reporting a bug. Again-- this behaviour is intentional and not a bug, but if you want a NEW switch in /echo to bypass to forcibly disable timestamp logging for a line, feel free to suggest it in the Feature Suggestions forum.