Are successor plan rules different for stock deals and corporate merge

[KJohnson]

Two companiies wish to merge. For a number of reasons they want to terminate one 401(k) plan prior tho the merger and distribute its assets. The remaining 401(k) plan would then cover the employees of the merged entity. As I read the successor plan regulations, if a termination takes place prior to a stock deal, then there is no successor plan problem because the control group for purposes of the successor plan rules is determined at the time of the termination. However, if the termination takes place prior to a merger there would be a problem because the same "employer" would then be maintaining another 401(k) plan.

Do other people have the same understanding? Isn't this a distinction without a real economic difference? What if immediately after the stock deal the company with the termnated 401(k) plan is liquidated?