1. Does anyone know anything about this? I've always thought it's one right to be known by whatever name one wants...???...
It is. However, all sorts of organisations don't like it, because it makes it more difficult to perform cross-checks on you. As long as you don't do it to defraud, however, it remains perfectly legal until the Identity Cards Act 2006 is fully in effect (and perhaps even then).
Change solicitor-he's talking rubbish. Simply fill in a Deed on change of name ( does not have to be a deed poll) with a short covering letter explaining reasons for name change - your passport will be back with you in the normal time.
He isn't talking rubbish, for the reasons noted above. Bureaucracies regard unusual personal choices as inherently suspicious.
The description of procedure by the guest is inaccurate, and implies a misunderstanding. The only purpose in (historically) executing a deed poll, or (in modern times) making a statutory declaration of your change of name, is to produce an officially recognised connection between your former name and your new one.
(Procedure explained here: http://www.adviceguide.org.uk/index/family_parent/family/change_of_name.htm
As far as shortening your name by dropping middle names is concerned, then in practice you can probably just do it, since your first and last names, your address and date of birth are what matter to most clerical systems, and no conflicts are likely to be created in any significant records.
If you aren't breaking any law, then your worry is how the system will cope. As long as you don't introduce any conflicting information, then the system is likely to accept a tacit change. Doing things the "official" way by statutory declaration might be an unnecessary complication.