I was looking at MTC.sbp and can't figure out why CHECK_MTL subroutine is there. It doesn't seem to do anything. No matter what, it's going to set &z_adjust to zero.

First line is commented out. Second line sets &zshift to zero.
If MSGBOX answer is NO, then &z_adjust = 0 * 0
if MSGBOX answer is YES, then &z_adjust = 0 * 1



CHECK_MTL:
'If &zshift = 0 Then GoSub MTL_ERROR
&zshift = 0
if &zero_to_bed = 0 then GoTo doaskbed
if &zero_to_bed = 1 then GoTo doaskbed
MSGBOX(Did you Zero to bed? ,YesNo,ZERO BIT?)
doaskbed:
if &msganswer = NO then &zero_to_bed = 0
if &msganswer = YES then &zero_to_bed = 1

&z_adjust = &zshift * &zero_to_bed
return