An idea: A more Representative Voting System that keeps the Constituency link

How can we have an electoral system that retains the local constituency link between the voter and MP but which is more representative than the First Past the Post/Winner Take All system?  My answer:
         In this system which has popped into my mind (for all I know other people may have thought of it before me), single member constituencies would be retained but the candidate with the most votes will not be guaranteed to be the new MP if he receives less than 50% of the vote.  Should no candidate receive a majority of the votes cast, whoever is to become the new MP would need the endorsement of another candidate who himself has enough votes to bridge the gap.  For example, if the candidate with the most votes gets 42% of the vote (candidate X), he or she will have to enter an agreement with another candidate who has received at least 8% of the popular vote (Candidate Y) for Candidate X to be over the line and become the new MP.

 ,Under this system, if within a year of X becoming the MP, Y feels that X, has not been keeping the promises that he made in their agreement, Y can withdraw his endorsement and the post of MP for the constituency will now be vacant.  A new MP will have to be selected from the list of candidates at the last election, and that new MP will need the endorsement of himself and a fellow candidate who received enough votes at the last election to get him over the 50% line.  If no such agreement can be made within, say 3 weeks of X being removed as MP, then a by-election will have to happen and the process will start fresh from there.

The benefits of such a system are great, in my opinion.  For starters, tactical voting would be unnecessary; every vote would count and that is, after all, what Democracy is all about .  It would also require common ground to be made whenever no single candidate gets a majority of votes cast; and that is only fair.  The link between the constituency voter and the serving MP will be preserved but more importantly the way the constituency voted at the last election will be relevant throughout the parliamentary term and the sitting MP, should he have been elected with fewer than 50% of the votes cast, will have to remain in touch with how his constituency voted.  Don't forget that due to tactical voting no longer being necessary under this system, there would no doubt be fewer constituencies in which single candidates get a majority of the votes cast.