Fun with unbalanced corpora

This came up in a pub conversation (as many of the best things do): should daddy longlegs (or long legs), another name for the crane fly in British English and the harvestman in American English, be pluralized as daddies longlegs?

My well-trained lexicographer’s response, of course, was ‘it really doesn’t matter’: it could be pluralized like that, or as daddy longlegses, or without alteration as daddy longlegs. But, in the interests of interest, here are the resulting (and no doubt massively noisy and so only slightly suggestive) results for number of Google hits:

Daddy longlegs: c124,000
Daddy long legs: c460,000
Daddies longlegs: 9
Daddies long legs: c391
Daddy longlegses: c216
Daddy long legses: c585
Daddies longlegses: 1 (!)
Daddies long legses: 0

Finding the unmutated plural is trickier, but “daddy longlegs are” returns c1780 hits, and “daddy longlegs have” c536.

The conclusions?

1. Plural forms with legses are more common than those with daddies.
2. If anywhere near accurate, daddy long(-)legs may be the commonest plural, suggesting that the plurality of the legs component may be tacitly extended to the whole lexical item.
3. It really doesn’t matter.