This depends upon your stats, actually. For your first 56, no, you won't find it easy to get BCS. Gear up with the white level 60 gear, and it is not that hard. With a full set of i190/i195 Ironworks, it is ridiculously easy. Titanium Nugget, for example, with 983 Craftsmanship, gets completed with one CS2, meaning that one can do a CZ, IQ, WN1, SH2, HTx5 initial set. Follow that with Manipulation, SH2, WN, and then some combination of HT and BT to leave enough CP for SH, GS, Inno, BB, and then a CS2, and you've got your 100%'d Nugget. That's with 936 base Control. As I said, full Ironworks i190/i195. Even without that though, I had gotten an IQ10 (without using PT on the two Goods I got!) on this rotation, which with much less Control would still allow for enough of a BB to 100% it.
That said, it may be easier, depending on level, to do a 70 durability recipe than a 35 or 40 durability recipe. Depending on how you use it, Waste Not 2 may be the best way to play Durability games based on the CP usage, but Master's Mend 2 is generally the best in terms of CP usage per Durability once you factor in practicality. The 70 Durability BCS hand ins will require a lot more in materials per craft, but tend to be worth a lot more BCS as well. Depending on the total number of Progress steps needed, you may start off one way or another :
CZ, IQ, SH2, RS, CS2, HTx3, SH2, HT, MM2, HTx3, SH2, HTx2, GS, Inno, BB, CS2
CZ, IQ, CS2, SH2, HTx5, MM2, SH2, HTx5, SH2, GS, Inno, BB, CS2
Or some variant thereupon, replacing HT's with PT's (early on) and BT's (later on) as CP and Condition permit. Another possible advantage of the 70 Durability recipes is that you have better control (through manually crafting yourself) just how much of your materials are HQ and how much are NQ. You are forced to rely on the luck of the draw for your Titanium Nugget materials, but when you craft the Titanium Ingot, Dragon Leather, Dhalmel Leather, Hardsilver Ingot, and the Grade 1 Dexterity Dissolvent yourself, you are better able to ensure that those refined materials are HQ. The necessity of which is gear dependent; the possibility of it is level dependent.
Personally, when I look at getting BCS, I do the same judgement as getting RCS : what gets me the most (or targeted) level of Scrip with the least hand ins? I'd rather do something for 160 BCS than three somethings for 70 BCS if all I want is 150 BCS.