Yep, the channel run in GW's 1939 is ass-easy. You can safley get through without even diving if you hug the French coast, and make your run at nighttime (I usually do it at ahead standard or full, at the narrowest points)
'Course, I havn't tried it any later, so I can't comment on the mines... but judging from how many times I've hit mines so far (Twice in one day!), it wouldn't be worth it later on, unless there was something
really juicy on the other side that you had to get to NOW