Fractional Share Paid in Cash

When a company splits stock, declares a stock dividend or merges,
the shareholder will often receive a small cash payment
in lieu of a fractional share. Although Publication 550
allocates a cost basis to the fractional share, I have
always declared the proceeds on Schedule D with a cost basis
of zero [though I know it is contrary to Publication 550
instructions]. This results in a small capital gain with no change
in the total cost of existing shares. Is this an acceptable
procedure to the IRS? They have never challenged my practice.

.