What is the difference between the expert testimony and the written opinions of the expert on electrical consumption of the extrusion and slitting lines?

With reference to the evidence of the experts, as well as the written opinions contained in their affidavits, it is my opinion that Mr. Dovey"s testimony carries more weight on this issue. I consider Mr. Rostant"s final figures to be rather high. However, I find persuasive Mr. Rostant"s opinion that electrical consumption by machinery other than the extrusion and slitting lines should be taken into account. I find that Mr. Dovey"s figures are rather low in this area. Based on the totality of the evidence on this issue, it is my opinion that an average of the expert"s figures should be used. I find support for this approach in the following comment by Dickson J. in Lewis v. Todd:1