cheers OvO, on 2015-September-16, 20:21, said:
1- E has a perfect 3♠ preempt. Almost textbook.
2-About 10-12 4 card support ; anything over 10+ hcp you start with a cuebid, showing you have 3+ card support and (10)11+ hcp. Cue means limit raise or better. Pd should continue as if cue is limit raise. If better responder makes another move. This is not the best method, but since you believe 3♠ can be both weak and 10-12 hcp at the same time, I believe you should just go with the basics for now.
3-As Gordon said, 4 NT is a very bad call vs a weak 3♠ with a balanced hand.
4-3♦ shows a hand with 4 card support and less than cue (less than 11) more than preempt (7-9 or bad 10). Do not worry about having 17+ hcp and support. This is included in "limit raise or better cue"
5-Starting overcall with 19 hcp is not the end of the world to me. I do it sometimes, my usual max overcall limit is 18. But holding 4 card ♥ on the side increases your chances to make game vs a little. Assume your pd had short spades and 4-5 hearts with 6-7 hcp, which he would pass. But I definitely can live with this overcall.
Cheers and have a nice day