It seems as though companies not required to capitalize costs under IRC Section 263A can deduct IBNR as long as they accrue it without having to fund same. Service companies such as accounting and consulting firms come to mind.

What other firms can take advantage of this departure from the 1972 U.S. Supreme Court decision involving General Dynamics?

This would not seem to be a VEBA question, since VEBAs are for funded welfare benefits, not unfunded ones. IRC 419 specifically requires that amounts must be "paid or accrued" for a specific tax year.

Why incur the cost of setting up and maintaining a VEBA if the same accelerated deduction results merely through obtaining an actuarial certification?

You may wish to peruse the Deloitte Washington Tax Bulletin dated April 13, 2009* which suggests this issue does have sometihng to do with VEBAs.

*retrievable from www.benefitslink.com

I perused the Deloitte Washington Tax Bulletin dated April 13, 2009. It relates to COBRA coverages and is found here: COBRA Guidance Highlights Potential Problem Areas
It does not seem to relate to your post.

go to http://benefitslink.com/articles/guests/washbull090413a.html

It seems as though companies not required to capitalize costs under IRC Section 263A can deduct IBNR as long as they accrue it without having to fund same. Service companies such as accounting and consulting firms come to mind.

The question is not WHETHER they have to fund it (that is a given), but WHEN. In general, the employer must pay such expenses before the end of the tax year. Under the rules described in the article, the employer, under IRC section 461(a), may claim a deduction for services provided by another person prior to the end of the year, even though the amount is not actually paid prior to the end of the tax year.

This contrasts with the rule announced in General Dynamics that in order to be deductible for the current year the amounts had to be paid before the end of the tax year. Sec. 419(c)(3)(B) refers to the time "when such benefit would be includible in the gross income of the employee if provided directly by the employer", which would be the year of payment. This rule still applies for reimbursements paid directly to employees, or for which employees must file claims to have the payment or reimbursement paid.