I know that the patterns are in use and have quite similar meanings. According with BNC, Google, dictionaries and what I myself read.
Do you normally/often/ever use the subjunctive form if need be (or even 'if need were :))
I am now writing an answer to an e-mail that, in fact, is a quite formal letter containing such extra phrases as ‘I should very much like to meet you sometime soon…’, ‘When you have received the <….> perhaps you could <…>’ and the like.
Which expression would be better to use if I want to express that by now (in my own understanding) I seem to have done all what was required by formal rules, but for some reasons I suppose that the other part can rise some additional (and essential!) requirements – just after reading my answer.
Does ‘…, if required’ express that?