Although to further answer your question regarding how spesh will help in methods, while it may appear that less than half othe spesh course will help with methods, the fact is that it will help in more than half, maybe up to two thirds of the methods course.
In the case of differentiation, antidifferentiation, areas under graphs, related rates which comrpise the calculus section of the methods course a sound understanding of the spesh material will make you feel like the methods stuff is elementary and basic and you should find that entire third of the course fairly simple.
Spesh will have trig in it and this includes graphing functions, solving trig equations as well as more advanced stuff. Again, after doing spesh trig you will likely not have a problem with methods trig because you need to get the fundamentals of trig right to be able to get the more advanced stuff right, so it is likely you'll be good at all the methods stuff
The other area spesh helps is with rational functions: their graphing and manipulation. Part of methods 3/4 is basically just 1/2 in that you still graph parabolas, logarithmic functions etc. Spesh will help a bit in understanding the graphing process as well as other things like addition of ordinates.
From my experience thus far in the year, doing spesh has made methods seem like a much easier subject, and while I warn against complacency, if you like maths and are good at it then spesh will be helpful imo.