kennethk,
I haven't digested your code but at a glance, your Benchmark is flawed for a couple of reasons. Here is the output of your code with the following lists 
my @list1 = qw(2 3 5 7 11 13 17 19 23 29);
my @list2 = qw(1 1 2 3 5 8 13 21 34 55 89);
__DATA__
3
4
4
5
6
8
11
16
24
37
58
92
6
6
7
8
10
13
18
26
39
60
94
8
8
9
10
12
15
20
28
41
62
96
12
12
13
14
16
19
24
32
45
66
100
14
14
15
16
18
21
26
34
47
68
102
18
18
19
20
22
25
30
38
51
72
106
20
20
21
22
24
27
32
40
53
74
108
24
24
25
26
28
31
36
44
57
78
112
30
30
31
32
34
37
42
50
63
84
118
4
6
8
12
14
18
20
24
30

[download]

Cheers - L~R

In reply to Re^2: Challenge: Sorting Sums Of Sorted Series by Limbic~Region
in thread Challenge: Sorting Sums Of Sorted Series by Limbic~Region

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