Photoshop make new spot color channel

Hi All

I am creating a new spot colour channel in Photoshop and am able to do it but it is very slow. It takes about 7 seconds to do it on a file which is about A3 cmyk and with four layers. By looking at the history I can tell it does each part of the creation of the channel as a separate step.

Does anyone know if there is a faster way of doing this?

tell application "Adobe Photoshop CS5.1"
	tell current document
		make new channel at end with properties {name:"PANTONE 186 C", kind:spot color channel, opacity:0.0, visible:true, channel color:{class:Lab color, value_L:44.0, value_a:68.0, value_b:38.0}}
	end tell
end tell

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