Also Giant’s Causeway’s second dam was by Roberto, by Hail to Reason, and has another cross to Hail to Reason through Halo, sire of Rahy’s dam Glorious Song. A lot of the Hail to Reason line were big, rawboned types (Dynaformer, anyone?) so that may be where it comes from.
Sorry for the duplication, apparently skydy and I were typing at the same time.