401(a)(26) with offset involving 2 db plan

We have a case where the client had a db plan for many years, which became very overfunded. A new db plan was created, with the idea of a carve out or offset between the plans. Plan A  covers 2 participants and provides a benefit of 6% x service accrual and plan B provides a benefit of 8% x participation. In Year 1& 2, the benefit accrued in plan A is fully offset by the Plan B accrual, and the question is how to satisfy 401(a)(26) for plan A for these years. From what I have studied, 401(a)(26) might not be satisfied until both plans can be aggregated for (a)(26). 

No replies so I'll bite.   The fact pattern or objective does not seem clear to me.  What is the legal basis for aggregating them under 401(a)(26)?  When "can they be" aggregated other than when/if they are merged?

The regs state that an offset arrangement satisfies 401(a)(26). Thus if an employee participates in plan A under the plan terms but due to the offset doesn't accrue a benefit, he is still counted for the a(26) testing.

A further question I have and can't find an answer anywhere: if a participant receives a 415 lump sum distribution, but is still employed and earning service and wages, is he still considered a participant and statutory employee for purposes of 401(a)(26)? It make1s a big difference in my testing!

He's not statutorily excludable so I don't know why he wouldn't be counted and in the test.   Isn't whether or not he benefits addressed by how 415 was handled in accordance with 1.410(b)-3(iii) and (iv)?  Which of course reverts back to how 415 was handled for a)(4) testing if that was necessary.   If (a)(4) testing wasn't necessary it seems that you have two choices, one taking 415 into consideration and the other ignoring 415.