Self Install

[#1]

Somebody I know who is a BT Broadband user is getting fttc ('Infinity') next week and has been asked to self-install.  An EE fttc self-install I saw a few weeks ago did not use a VDSL interstitial filter.  Is this the way things are going? 

[#2]

Pretty much. There is no requirement for an engineer to visit and sort things out to ensure people get the best chance of getting an optimal speed.
From the WBC_FTTC_Handbook_Issue_12.pdf page 22

Quote

When customers order Self Install they should understand that there is a higher risk of the line being impacted with wiring issues and End Users getting lower line and throughput rates. We recommend that CPs use Range B Broadband Availability Checker (BBAC) values when providing estimated speeds to their customers.

Also BT SIN 498 (available from http://www.btplc.com/sinet/) does allow for a filter at each socket style arrangement.
Edit: I also spotted this recently: Proof of Concept trial for CPs to Install NTEs
So perhaps in future it'll be the ISP who will be able to provide the SSFP and NTE5 to fit it on if wanted.

[#3]

Yep, a few companies are using fibre self install. Generally you'll find these with all-in-one modem/routers