It makes a difference because it will determine the amount of credit
you receive. The sharper the skew, the more the credit. Also, the
sharper the skew, the less risk you are taking on the vertical.
For example. Stock is at 97 and you sell the Dec 100 call and buy the
Dec 105 call for a 1.00 credit. Now if the stock moves against you,
because of the steepness of that skew, you might be able to get out of
this spread with minimal loss because at 100, the Dec 100 call will now
be ATM and may have a substantial drop in implied vols. Now, the
position still carried short deltas, however, you will lose less money
then you would if you sold into a neg call skew where the vol would
actually INCREASE going into the ATM strike.
Now, you might think these are all petty details, I assure you they are
not. Like I mentioned at the last meeting, these nickels and dimes do
add up at the end of the year, and for most traders, they make the
difference between making money on the year and losing money.
I understand the idea of looking at your risk from the standpoint of
max loss on the dif between the strikes, minus the credit. But a
trader should NEVER take the max loss on any position. That is why you
trade, to avoid that scenario. You manage the risk to minimize the
losses. You just don't accept the max loss. That is throwing away
money.
John