The small catamaran fits just millimeters inside the allowed maximum length prescribed in the Protocol governing the 34th America's Cup, to restrict the use of 'surrogate' boats, or near full size test platforms for the AC72 class.
Oracle Team USA has a pair of AC45's (specifically exempted under the Protocol) however they cannot have hull shape changes or other changes that would take them outside of the AC45 class rule.
The SL33's offer much more flexibility albeit at at less than half size. Little has been seen on video of the SL33's in action - until now.
Skipper Dean Barker explains how they have been used as a development platform.