I think that if you're swaying, it matters less than it would otherwise because you're doing so much more to counteract whatever boost in fertility/boy friendliness that the seasons seem to trigger.
You make a great point about it potentially taking months to conceive...I totally think you need to do what is right for you and your family first because you never know, you may not even get pg that first month or even first few months.
That having been said, for those who have a lot of leeway in deciding when to try, it makes some sense to go with the seasons but there are certainly TONS of opposites (I have TWO.)