@Private:
Have just started my first game as the allies and been surprised by a G1 purchase of an AC, DD & Sub for sz 112. As UK I am already feeling nervous! Even though I believe sea lion can only work if I fail to react to that danger, but my opponent is so much more experienced than I am.
AC/DD/sub is a solid G1 buy even if he has no intention of doing Sealion. It cements the dominance of the German navy in the North Sea and forces UK to invest most of his first round buy into units that won’t see actual action until many rounds later.
Personally though I’ve stopped buying the DD and sub and just buy the AC, holding onto the extra IPC helps to keep opponents guessing, and you can always buy the DD/sub on G2 if you really want to yet preserve the option of spending that capital on other things, such as land units to attack Russia, or on transports.