concurring:
I concur in Judge Wisdom’s persuasive and scholarly opinion for the Court. I append these further comments merely to reflect my understanding that we do not hold the erroneous exclusion of evidence of a challenged design’s conformance to industry custom in a Texas law strict liability products action is normally harmless, but rather that such erroneous exclusion was harmless under the particular facts of this case, especially since the real contest at trial was whether the skidder struck the victim and since standards evidence was admitted. As Judge Wisdom indicates, evidence that a product’s design conforms to or deviates from industry custom, though not dispositive, may nevertheless be relevant in determining whether the product is unreasonably dangerous under the risk-utility balancing test. That potential relevance may be twofold. First, industry custom will usually tend to show the collective judgment of the industry on the subject, and in this respect it has the same character of relevance as a professional society standard, though the relevance is more attenuated since factors other than product safety are more likely to influence the custom than the standard. Second, it will in many instances, though by no means all, tend to show general user experience with and expectations of product handling or performance in respect to the design characteristics at issue; and frequently the extent of the risk actually posed by a given product design characteristic will be affected by the degree to which it causes the product’s operation and performance to conform to general user experience and expectations. Whether in a given case industry custom is relevant under either of the above theories, and if so the degree of its probative value, will naturally depend, among other things, on the nature of the product, the particular design characteristics at issue and the industry custom. However, it is not difficult to imagine cases where the probative value may be substantial and, depending on the trial posture, where exclusion of evidence of such custom may not only be error but also reversible *351error. I join my distinguished colleagues in their determination that reversible error is not presented by this record.