#!/bin/ksh
if [ $# -gt 0 ]
then	rem_list="$@"
else	rem_list="dxv1 k2"
fi
awk -v del="$rem_list" '
BEGIN {	# Split del string into remhdr[] (indexed 1..nrem)...
	nrem = split(del, remhdr)
	# Create rem[] (indexed by titles of fields to be removed).
	for(i = 1; i <= nrem; i++) {
		rem[remhdr[i]]
		delete remhdr[i]
	}
	# Set OFS
	OFS = "\t"
}
NR <= 3 {
	# Read header lines into hdr[]...
	for(i = 1; i <= NF; i++)
		hdr[NR, i] = $i
	if(NR == 3) {
		# Create array of output fields to delete: od[]...
		for(i = 1; i <= NF; i++)
			if(hdr[3, i] in rem) {
				od[i]
				odc++
				delete rem[hdr[3,i]]
				nrem--
			}
		if(nrem) {
			for(i in rem)
				printf("*Field heading \"%s\" not found.*\n", i)
			printf("** Processing aborted. **\n");
			exit 1
		}
		# Print updated headers...
		for(i = 1; i <= 3; i++) {
			oc = NF - odc
			for(j = 1; j <= NF; j++)
				if(!(j in od))
					printf("%s%s", hdr[i, j],
						(--oc) ? OFS : ORS)
		}
	}
	next
}
{	# Print data lines...
	for(i in od)
		$i = ""
	$0 = $0
	$1 = $1
	print
}' original_f0_RSV_1912_A_S1v6_RI7_1916_15-01-10.txt

real	0m0.07s
user	0m0.07s
sys	0m0.01s

real	0m0.06s
user	0m0.06s
sys	0m0.00s

if [ $# -gt 0 ]
then	rem_list="$@"
else	rem_list="dxv1 k2"
fi
awk -v del="$rem_list" '

awk -v del="${LIST_TO_REMOVE[@]}" '