biblatex: \textcite author formatting vs. bibliography author formatting

Question

For LaTeX citations, I use biblatex/babel. The journal for which I'm writing requires a bibliography with authors formatted as follows:

Guyton AC, Hall JE.

That is, with no "and" before the last author. I did manage this (see example below), however, in \textcite, "and" is also gone now...

Questions

1. Is it possible to remove "and" in the bibliography, but leave it in \textcite.
2. Previously, I used \textcite together with the authoryear style. Using a solution also posted on this website, I was able to put multiple sources in one \textcite, and biblatex would place commas and an "and" at the appropriate places. Is it possible to adapt this solution for numeric citation styles?
3. Is there a way to make all authors (and the commas in between them) bold in the bibliography?

\documentclass[a4paper]{article}
\usepackage[american]{babel}
\usepackage[
  terseinits=true,
  firstinits=true,
  backend=biber,
  style=numeric
]{biblatex}

%Put initials after names...
\DeclareNameAlias{sortname}{last-first}
\DeclareNameAlias{default}{last-first}    

%Remove "and" before last name. However, this also removes "and" in a textcite...
\renewcommand*{\finalnamedelim}{\addcomma\space}

%I also removed the commas between last names and initials (http://tex.stackexchange.com/questions/17583/biblatex-remove-commas-between-last-and-first-names-in-bibliography). This is however not needed for a minimum working example.

%Generate a test bibliography
\usepackage{filecontents}
\begin{filecontents*}{database.bib}
@BOOK{Guyton2006,
  title = {Textbook of Medical Physiology},
  publisher = {W.B. Saunders},
  year = {2006},
  author = {Arthur C. Guyton and John E. Hall},
  address = {Philadelphia, Pennsylvania},
  edition = {11th Edition}
}
\end{filecontents*}

\bibliography{database.bib}

%Some biber compatibility things (from http://tex.stackexchange.com/questions/21711/setting-up-winedt-6-0-and-miktex-to-run-biblatex-and-biber)...
\makeatletter
    \providecommand\bibstyle@faked{}
    \providecommand\bibdata@faked{}
    \AtBeginDocument{%
    \immediate\write\@mainaux{\noexpand\bibstyle@faked}%
    \immediate\write\@mainaux{\noexpand\bibdata@faked}}
\makeatother

\begin{document}
The following sentence contains a textcite example. \textcite{Guyton2006} wrote a comprehensive textbook.
\printbibliography
\end{document}

Answer 1

Ad question 1: Simply use

\AtBeginBibliography{%
  \renewcommand*{\finalnamedelim}{\addcomma\space}%
}

Answer 2

Question 1 can be resolved by using the \ifcurrentname test in a redefinition of \finalnamedelim.

A solution for question 3 could be restricted to the name list at the beginning of each bibliography entry. This name list depends on the availability of author, editor and translator as well as the entry type. In the code below I've taken a lazy way out using egreg's patch commands and a flag to indicate when any given name list should be set in boldface.

Question 2 might be better addressed in another post, especially if you want a solution that will work for any standard numeric style.

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[american]{babel}
\usepackage{csquotes}
\usepackage[style=numeric,terseinits=true,firstinits=true]{biblatex}
\usepackage{hyperref}

% Define egreg's patch commands
% (or just use \xpatchbibmacro et al. with xpatch package)
\makeatletter
\def\act@on@bibmacro#1#2{%
  \expandafter#1\csname abx@macro@\detokenize{#2}\endcsname}
\def\patchbibmacro{\act@on@bibmacro\patchcmd}
\def\pretobibmacro{\act@on@bibmacro\pretocmd}
\def\apptobibmacro{\act@on@bibmacro\apptocmd}
\def\showbibmacro{\act@on@bibmacro\show}
\makeatother

% Omit commas in name:last-first bibmacro
\patchbibmacro{name:last-first}
  {\ifblank{#2}{}{\addcomma\bibnamedelimd\mkbibnamefirst{#2}\isdot}}{}{}{}
\patchbibmacro{name:last-first}{\ifblank{#2#3}{}{\addcomma}}{}{}{}

% Set first name list in boldface
\newtoggle{bbx:bold}
\AtEveryBibitem{\toggletrue{bbx:bold}}
\pretobibmacro{name:last-first}{\iftoggle{bbx:bold}{\bfseries}{}}{}{}
\apptobibmacro{name:last-first}
  {\ifnumequal{\value{listcount}}{\value{liststop}}
     {\global\togglefalse{bbx:bold}}
     {}}
  {}{}

\DeclareNameAlias{default}{last-first}
\DeclareNameAlias{sortname}{last-first}

% Omit "and" from \finalnamedelim in full citations and bibliography entries
\renewcommand*{\finalnamedelim}{%
  \ifcurrentname{labelname}
    {\ifnumgreater{\value{liststop}}{2}{\finalandcomma}{}%
     \addspace\bibstring{and}\space}
    {\addcomma\space}}

\addbibresource{biblatex-examples.bib}

\begin{document}
\null\vfill\noindent
Filler text.\footfullcite{companion}
\textcite{companion,coleridge,gaonkar} show that...
\textcites{companion}[10--15]{coleridge} show that...
\citeauthor{companion} show that...
\printbibliography
\end{document}

Answer 3

Add this to your preamble:

% delimiter switching for cite and textcite
\let\olddelim\finalnamedelim
\let\oldtextcite\textcite

\newcommand{\switchdelim}[1]{\renewcommand*{\finalnamedelim}{#1}}

% set up the default
\switchdelim{\addcomma\space}

% wrap the textcite command to reversibly switch the delimiter
\renewcommand{\textcite}[1]{%
{%
\renewcommand{\textbf}{}% suppress bold faced names in the running text
\switchdelim{\olddelim}%
\oldtextcite{#1}%
\switchdelim{\addcomma\space}%
}%
}

% format the author names
\renewcommand{\mkbibnamelast}{\textbf}
\renewcommand{\mkbibnamefirst}{\textbf}
\renewcommand{\mkbibnameprefix}{\textbf}
\renewcommand{\mkbibnameaffix}{\textbf}

% sneak a textbf into the definition of addcomma. This may be
% too much of a low-level hack, I hope there is a cleaner 
% way for doing this, but it seems to work.  
\makeatletter 
\protected\def\blx@imc@addcomma{\textbf{\blx@addpunct{comma}}}
\makeatother

That gives: