I don't think NCPlot will check for this?
There's a thread on emastercam about missing a parenthesis on a 30 fanuc control with big consequences.
One Little Typo, One Big Crash - eMastercam.com
Someone says that vericut can check for this - it may be worth looking to implement the same feature?
I wasn't even aware that some controls would allow multiple line comments! Thanks for the heads up, I will be adding this...