I have problems when black places his bishop on d6 in the London. Take for instance the following game:
r1bq1rk1/p2n1ppp/2n1p3/1p1pP3/2p5/2P1P1B1/PPBN1PPP/R2QK2R w KQ - 1 12
1. d4 d5 2. Bf4 { D00 Queen's Pawn Game: Mason Variation } e6 3. e3 Bd6 4. Bg3 Nf6 5. Bd3 O-O 6. Nd2 c5 7. c3 c4 8. Bc2 Nc6 9. Ngf3 b5 10. Ne5 Bxe5 11. dxe5 Nd7
The question of what to do with ...Bd6 comes already in movement 4. Theory advises White to avoid taking it, as that will bring Black's Queen into play. Instead, White should retreat his bishop to g3, or even leave it on f4. First problem is, with the bishop in g3, White can't castle kingside while the d6-g3 diagonal is open.
The second problem is that placing a piece on e5 should be White's main plan with the London, but with Black's bishop on d6, that's not possible, as Black can exchange any piece post there by White. Even worse, if White ends up with a pawn there, as in this game, this pawn will end up being very hard to defend for White. Or it will have to be defended with f2-f4, weakening White's kingside and blocking White's bishop if it's still on g3.
So my question is how to deal with Black's bishop on d6 addressing these two problems?