Thanks jcl. I understand that spread, leverage, etc. depend on the broker and not the optimal parameters. What has me confused is the reverse question: Don't the optimal parameters depend on the spread, leverage, etc. of the broker?

In other words, for the same strategy the optimal parameters determined using one broker's spread, leverage, etc. will be different from the optimal parameters determined using another broker's (or account's) spread, leverage, etc., correct?

Thanks.